Auto merge of #16235 - upsuper:bug1351957, r=heycam

Create URLExtraData for holding base uri, referrer, and principal

This is the Servo side change of [bug 1351957](https://bugzilla.mozilla.org/show_bug.cgi?id=1351957) which has been reviewed on Bugzilla.

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12 files changed, 243 insertions, 392 deletions

diff --git a/components/style/build_gecko.rs b/components/style/build_gecko.rs
index 287698adc52..fa7142b69a2 100644
--- a/components/style/build_gecko.rs
+++ b/components/style/build_gecko.rs
@@ -367,7 +367,6 @@ mod bindings {
             "nsCursorImage",
             "nsFont",
             "nsIAtom",
-            "nsIURI",
             "nsMainThreadPtrHandle",
             "nsMainThreadPtrHolder",
             "nsMargin",
@@ -604,10 +603,8 @@ mod bindings {
             "RawGeckoPresContext",
             "RawGeckoPresContextOwned",
             "RawGeckoStyleAnimationList",
-            "GeckoParserExtraData",
+            "RawGeckoURLExtraData",
             "RefPtr",
-            "ThreadSafeURIHolder",
-            "ThreadSafePrincipalHolder",
             "CSSPseudoClassType",
             "TraversalRootBehavior",
             "FontFamilyList",
@@ -630,7 +627,6 @@ mod bindings {
             "nsCursorImage",
             "nsFont",
             "nsIAtom",
-            "nsIURI",
             "nsMediaFeature",
             "nsRestyleHint",
             "nsStyleBackground",
diff --git a/components/style/gecko/url.rs b/components/style/gecko/url.rs
index b1550486cdf..f6d1e0ce244 100644
--- a/components/style/gecko/url.rs
+++ b/components/style/gecko/url.rs
@@ -5,8 +5,8 @@
 //! Common handling for the specified value CSS url() values.
 
 use cssparser::CssStringWriter;
-use gecko_bindings::structs::ServoBundledURI;
-use gecko_bindings::sugar::refptr::{GeckoArcPrincipal, GeckoArcURI};
+use gecko_bindings::structs::{ServoBundledURI, URLExtraData};
+use gecko_bindings::sugar::refptr::RefPtr;
 use parser::ParserContext;
 use std::borrow::Cow;
 use std::fmt::{self, Write};
@@ -22,12 +22,8 @@ pub struct SpecifiedUrl {
     /// really large.
     serialization: Arc<String>,
 
-    /// The base URI.
-    pub base: GeckoArcURI,
-    /// The referrer.
-    pub referrer: GeckoArcURI,
-    /// The principal that originated this URI.
-    pub principal: GeckoArcPrincipal,
+    /// The URL extra data.
+    pub extra_data: RefPtr<URLExtraData>,
 }
 
 impl SpecifiedUrl {
@@ -39,7 +35,7 @@ impl SpecifiedUrl {
                                  context: &ParserContext)
                                  -> Result<Self, ()> {
         let extra = &context.extra_data;
-        if extra.base.is_none() || extra.referrer.is_none() || extra.principal.is_none() {
+        if extra.data.is_none() {
             // FIXME(heycam) should ensure we always have a principal, etc.,
             // when parsing style attributes and re-parsing due to CSS
             // Variables.
@@ -49,9 +45,7 @@ impl SpecifiedUrl {
 
         Ok(SpecifiedUrl {
             serialization: Arc::new(url.into_owned()),
-            base: extra.base.as_ref().unwrap().clone(),
-            referrer: extra.referrer.as_ref().unwrap().clone(),
-            principal: extra.principal.as_ref().unwrap().clone(),
+            extra_data: extra.data.as_ref().unwrap().clone(),
         })
     }
 
@@ -88,9 +82,7 @@ impl SpecifiedUrl {
         ServoBundledURI {
             mURLString: ptr,
             mURLStringLength: len as u32,
-            mBaseURI: self.base.get(),
-            mReferrer: self.referrer.get(),
-            mPrincipal: self.principal.get(),
+            mExtraData: self.extra_data.get(),
         }
     }
 }
diff --git a/components/style/gecko_bindings/bindings.rs b/components/style/gecko_bindings/bindings.rs
index c5896b01127..89010477bee 100644
--- a/components/style/gecko_bindings/bindings.rs
+++ b/components/style/gecko_bindings/bindings.rs
@@ -17,10 +17,8 @@ use gecko_bindings::structs::RawServoDeclarationBlock;
 use gecko_bindings::structs::RawGeckoPresContext;
 use gecko_bindings::structs::RawGeckoPresContextOwned;
 use gecko_bindings::structs::RawGeckoStyleAnimationList;
-use gecko_bindings::structs::GeckoParserExtraData;
+use gecko_bindings::structs::RawGeckoURLExtraData;
 use gecko_bindings::structs::RefPtr;
-use gecko_bindings::structs::ThreadSafeURIHolder;
-use gecko_bindings::structs::ThreadSafePrincipalHolder;
 use gecko_bindings::structs::CSSPseudoClassType;
 use gecko_bindings::structs::TraversalRootBehavior;
 use gecko_bindings::structs::FontFamilyList;
@@ -43,7 +41,6 @@ use gecko_bindings::structs::nsChangeHint;
 use gecko_bindings::structs::nsCursorImage;
 use gecko_bindings::structs::nsFont;
 use gecko_bindings::structs::nsIAtom;
-use gecko_bindings::structs::nsIURI;
 use gecko_bindings::structs::nsMediaFeature;
 use gecko_bindings::structs::nsRestyleHint;
 use gecko_bindings::structs::nsStyleBackground;
@@ -371,20 +368,6 @@ extern "C" {
     pub fn Servo_StyleSet_Drop(ptr: RawServoStyleSetOwned);
 }
 extern "C" {
-    pub fn Gecko_AddRefPrincipalArbitraryThread(aPtr:
-                                                    *mut ThreadSafePrincipalHolder);
-}
-extern "C" {
-    pub fn Gecko_ReleasePrincipalArbitraryThread(aPtr:
-                                                     *mut ThreadSafePrincipalHolder);
-}
-extern "C" {
-    pub fn Gecko_AddRefURIArbitraryThread(aPtr: *mut ThreadSafeURIHolder);
-}
-extern "C" {
-    pub fn Gecko_ReleaseURIArbitraryThread(aPtr: *mut ThreadSafeURIHolder);
-}
-extern "C" {
     pub fn Gecko_ChildrenCount(node: RawGeckoNodeBorrowed) -> u32;
 }
 extern "C" {
@@ -446,9 +429,9 @@ extern "C" {
     pub fn Gecko_LoadStyleSheet(loader: *mut Loader,
                                 parent: *mut ServoStyleSheet,
                                 import_rule: RawServoImportRuleBorrowed,
-                                base_uri: *mut nsIURI, url_bytes: *const u8,
-                                url_length: u32, media_bytes: *const u8,
-                                media_length: u32);
+                                base_url_data: *mut RawGeckoURLExtraData,
+                                url_bytes: *const u8, url_length: u32,
+                                media_bytes: *const u8, media_length: u32);
 }
 extern "C" {
     pub fn Gecko_MaybeCreateStyleChildrenIterator(node: RawGeckoNodeBorrowed)
@@ -892,6 +875,14 @@ extern "C" {
     pub fn Gecko_ReleaseCSSURLValueArbitraryThread(aPtr: *mut URLValue);
 }
 extern "C" {
+    pub fn Gecko_AddRefURLExtraDataArbitraryThread(aPtr:
+                                                       *mut RawGeckoURLExtraData);
+}
+extern "C" {
+    pub fn Gecko_ReleaseURLExtraDataArbitraryThread(aPtr:
+                                                        *mut RawGeckoURLExtraData);
+}
+extern "C" {
     pub fn Gecko_FillAllBackgroundLists(layers: *mut nsStyleImageLayers,
                                         max_len: u32);
 }
@@ -1387,10 +1378,8 @@ extern "C" {
                                           data: *const nsACString,
                                           parsing_mode: SheetParsingMode,
                                           base_url: *const nsACString,
-                                          base: *mut ThreadSafeURIHolder,
-                                          referrer: *mut ThreadSafeURIHolder,
-                                          principal:
-                                              *mut ThreadSafePrincipalHolder)
+                                          extra_data:
+                                              *mut RawGeckoURLExtraData)
      -> RawServoStyleSheetStrong;
 }
 extern "C" {
@@ -1404,10 +1393,8 @@ extern "C" {
                                            gecko_stylesheet:
                                                *mut ServoStyleSheet,
                                            data: *const nsACString,
-                                           base: *mut ThreadSafeURIHolder,
-                                           referrer: *mut ThreadSafeURIHolder,
-                                           principal:
-                                               *mut ThreadSafePrincipalHolder);
+                                           extra_data:
+                                               *mut RawGeckoURLExtraData);
 }
 extern "C" {
     pub fn Servo_StyleSheet_HasRules(sheet: RawServoStyleSheetBorrowed)
@@ -1563,13 +1550,13 @@ extern "C" {
     pub fn Servo_ParseProperty(property: *const nsACString,
                                value: *const nsACString,
                                base: *const nsACString,
-                               data: *const GeckoParserExtraData)
+                               data: *mut RawGeckoURLExtraData)
      -> RawServoDeclarationBlockStrong;
 }
 extern "C" {
     pub fn Servo_ParseEasing(easing: *const nsAString,
                              base: *const nsACString,
-                             data: *const GeckoParserExtraData,
+                             data: *mut RawGeckoURLExtraData,
                              output: nsTimingFunctionBorrowedMut) -> bool;
 }
 extern "C" {
@@ -1624,7 +1611,7 @@ extern "C" {
 extern "C" {
     pub fn Servo_ParseStyleAttribute(data: *const nsACString,
                                      base: *const nsACString,
-                                     extraData: *const GeckoParserExtraData)
+                                     extra_data: *mut RawGeckoURLExtraData)
      -> RawServoDeclarationBlockStrong;
 }
 extern "C" {
@@ -1692,8 +1679,7 @@ extern "C" {
                                               value: *const nsACString,
                                               is_important: bool,
                                               base: *const nsACString,
-                                              data:
-                                                  *const GeckoParserExtraData)
+                                              data: *mut RawGeckoURLExtraData)
      -> bool;
 }
 extern "C" {
@@ -1704,7 +1690,7 @@ extern "C" {
                                                   is_important: bool,
                                                   base: *const nsACString,
                                                   data:
-                                                      *const GeckoParserExtraData)
+                                                      *mut RawGeckoURLExtraData)
      -> bool;
 }
 extern "C" {
diff --git a/components/style/gecko_bindings/structs_debug.rs b/components/style/gecko_bindings/structs_debug.rs
index 2451724ac57..3cb0c48012b 100644
--- a/components/style/gecko_bindings/structs_debug.rs
+++ b/components/style/gecko_bindings/structs_debug.rs
@@ -5224,6 +5224,49 @@ pub mod root {
             #[derive(Debug, Copy, Clone)]
             pub struct ImageLoader([u8; 0]);
             #[repr(C)]
+            #[derive(Debug)]
+            pub struct URLExtraData {
+                pub mRefCnt: root::mozilla::ThreadSafeAutoRefCnt,
+                pub mBaseURI: root::RefPtr<root::nsIURI>,
+                pub mReferrer: root::RefPtr<root::nsIURI>,
+                pub mPrincipal: root::RefPtr<root::nsIPrincipal>,
+            }
+            pub type URLExtraData_HasThreadSafeRefCnt =
+                root::mozilla::TrueType;
+            #[test]
+            fn bindgen_test_layout_URLExtraData() {
+                assert_eq!(::std::mem::size_of::<URLExtraData>() , 32usize ,
+                           concat ! (
+                           "Size of: " , stringify ! ( URLExtraData ) ));
+                assert_eq! (::std::mem::align_of::<URLExtraData>() , 8usize ,
+                            concat ! (
+                            "Alignment of " , stringify ! ( URLExtraData ) ));
+                assert_eq! (unsafe {
+                            & ( * ( 0 as * const URLExtraData ) ) . mRefCnt as
+                            * const _ as usize } , 0usize , concat ! (
+                            "Alignment of field: " , stringify ! (
+                            URLExtraData ) , "::" , stringify ! ( mRefCnt )
+                            ));
+                assert_eq! (unsafe {
+                            & ( * ( 0 as * const URLExtraData ) ) . mBaseURI
+                            as * const _ as usize } , 8usize , concat ! (
+                            "Alignment of field: " , stringify ! (
+                            URLExtraData ) , "::" , stringify ! ( mBaseURI )
+                            ));
+                assert_eq! (unsafe {
+                            & ( * ( 0 as * const URLExtraData ) ) . mReferrer
+                            as * const _ as usize } , 16usize , concat ! (
+                            "Alignment of field: " , stringify ! (
+                            URLExtraData ) , "::" , stringify ! ( mReferrer )
+                            ));
+                assert_eq! (unsafe {
+                            & ( * ( 0 as * const URLExtraData ) ) . mPrincipal
+                            as * const _ as usize } , 24usize , concat ! (
+                            "Alignment of field: " , stringify ! (
+                            URLExtraData ) , "::" , stringify ! ( mPrincipal )
+                            ));
+            }
+            #[repr(C)]
             pub struct URLValueData__bindgen_vtable {
             }
             #[repr(C)]
@@ -5232,10 +5275,8 @@ pub mod root {
                 pub vtable_: *const URLValueData__bindgen_vtable,
                 pub mRefCnt: root::mozilla::ThreadSafeAutoRefCnt,
                 pub mURI: root::nsMainThreadPtrHandle<root::nsIURI>,
-                pub mBaseURI: root::nsMainThreadPtrHandle<root::nsIURI>,
                 pub mString: root::RefPtr<root::nsStringBuffer>,
-                pub mReferrer: root::nsMainThreadPtrHandle<root::nsIURI>,
-                pub mOriginPrincipal: root::nsMainThreadPtrHandle<root::nsIPrincipal>,
+                pub mExtraData: root::RefPtr<root::mozilla::css::URLExtraData>,
                 pub mURIResolved: bool,
                 pub mIsLocalRef: bool,
             }
@@ -5243,7 +5284,7 @@ pub mod root {
                 root::mozilla::TrueType;
             #[test]
             fn bindgen_test_layout_URLValueData() {
-                assert_eq!(::std::mem::size_of::<URLValueData>() , 64usize ,
+                assert_eq!(::std::mem::size_of::<URLValueData>() , 48usize ,
                            concat ! (
                            "Size of: " , stringify ! ( URLValueData ) ));
                 assert_eq! (::std::mem::align_of::<URLValueData>() , 8usize ,
@@ -5261,40 +5302,27 @@ pub mod root {
                             "Alignment of field: " , stringify ! (
                             URLValueData ) , "::" , stringify ! ( mURI ) ));
                 assert_eq! (unsafe {
-                            & ( * ( 0 as * const URLValueData ) ) . mBaseURI
-                            as * const _ as usize } , 24usize , concat ! (
-                            "Alignment of field: " , stringify ! (
-                            URLValueData ) , "::" , stringify ! ( mBaseURI )
-                            ));
-                assert_eq! (unsafe {
                             & ( * ( 0 as * const URLValueData ) ) . mString as
-                            * const _ as usize } , 32usize , concat ! (
+                            * const _ as usize } , 24usize , concat ! (
                             "Alignment of field: " , stringify ! (
                             URLValueData ) , "::" , stringify ! ( mString )
                             ));
                 assert_eq! (unsafe {
-                            & ( * ( 0 as * const URLValueData ) ) . mReferrer
-                            as * const _ as usize } , 40usize , concat ! (
+                            & ( * ( 0 as * const URLValueData ) ) . mExtraData
+                            as * const _ as usize } , 32usize , concat ! (
                             "Alignment of field: " , stringify ! (
-                            URLValueData ) , "::" , stringify ! ( mReferrer )
+                            URLValueData ) , "::" , stringify ! ( mExtraData )
                             ));
                 assert_eq! (unsafe {
                             & ( * ( 0 as * const URLValueData ) ) .
-                            mOriginPrincipal as * const _ as usize } , 48usize
-                            , concat ! (
-                            "Alignment of field: " , stringify ! (
-                            URLValueData ) , "::" , stringify ! (
-                            mOriginPrincipal ) ));
-                assert_eq! (unsafe {
-                            & ( * ( 0 as * const URLValueData ) ) .
-                            mURIResolved as * const _ as usize } , 56usize ,
+                            mURIResolved as * const _ as usize } , 40usize ,
                             concat ! (
                             "Alignment of field: " , stringify ! (
                             URLValueData ) , "::" , stringify ! ( mURIResolved
                             ) ));
                 assert_eq! (unsafe {
                             & ( * ( 0 as * const URLValueData ) ) .
-                            mIsLocalRef as * const _ as usize } , 57usize ,
+                            mIsLocalRef as * const _ as usize } , 41usize ,
                             concat ! (
                             "Alignment of field: " , stringify ! (
                             URLValueData ) , "::" , stringify ! ( mIsLocalRef
@@ -5307,7 +5335,7 @@ pub mod root {
             }
             #[test]
             fn bindgen_test_layout_URLValue() {
-                assert_eq!(::std::mem::size_of::<URLValue>() , 64usize ,
+                assert_eq!(::std::mem::size_of::<URLValue>() , 48usize ,
                            concat ! ( "Size of: " , stringify ! ( URLValue )
                            ));
                 assert_eq! (::std::mem::align_of::<URLValue>() , 8usize ,
@@ -5323,7 +5351,7 @@ pub mod root {
             }
             #[test]
             fn bindgen_test_layout_ImageValue() {
-                assert_eq!(::std::mem::size_of::<ImageValue>() , 120usize ,
+                assert_eq!(::std::mem::size_of::<ImageValue>() , 104usize ,
                            concat ! ( "Size of: " , stringify ! ( ImageValue )
                            ));
                 assert_eq! (::std::mem::align_of::<ImageValue>() , 8usize ,
@@ -5331,12 +5359,12 @@ pub mod root {
                             "Alignment of " , stringify ! ( ImageValue ) ));
                 assert_eq! (unsafe {
                             & ( * ( 0 as * const ImageValue ) ) . mRequests as
-                            * const _ as usize } , 64usize , concat ! (
+                            * const _ as usize } , 48usize , concat ! (
                             "Alignment of field: " , stringify ! ( ImageValue
                             ) , "::" , stringify ! ( mRequests ) ));
                 assert_eq! (unsafe {
                             & ( * ( 0 as * const ImageValue ) ) . mInitialized
-                            as * const _ as usize } , 112usize , concat ! (
+                            as * const _ as usize } , 96usize , concat ! (
                             "Alignment of field: " , stringify ! ( ImageValue
                             ) , "::" , stringify ! ( mInitialized ) ));
             }
@@ -26466,6 +26494,7 @@ pub mod root {
     pub type RawGeckoElement = root::mozilla::dom::Element;
     pub type RawGeckoDocument = root::nsIDocument;
     pub type RawGeckoPresContext = root::nsPresContext;
+    pub type RawGeckoURLExtraData = root::mozilla::css::URLExtraData;
     pub type RawGeckoKeyframeList = root::nsTArray<root::mozilla::Keyframe>;
     pub type RawGeckoComputedKeyframeValuesList =
         root::nsTArray<root::nsTArray<root::mozilla::PropertyStyleAnimationValuePair>>;
@@ -26709,21 +26738,16 @@ pub mod root {
     impl Clone for nsMediaFeature {
         fn clone(&self) -> Self { *self }
     }
-    pub type ThreadSafePrincipalHolder =
-        root::nsMainThreadPtrHolder<root::nsIPrincipal>;
-    pub type ThreadSafeURIHolder = root::nsMainThreadPtrHolder<root::nsIURI>;
     #[repr(C)]
     #[derive(Debug, Copy)]
     pub struct ServoBundledURI {
         pub mURLString: *const u8,
         pub mURLStringLength: u32,
-        pub mBaseURI: *mut root::ThreadSafeURIHolder,
-        pub mReferrer: *mut root::ThreadSafeURIHolder,
-        pub mPrincipal: *mut root::ThreadSafePrincipalHolder,
+        pub mExtraData: *mut root::mozilla::css::URLExtraData,
     }
     #[test]
     fn bindgen_test_layout_ServoBundledURI() {
-        assert_eq!(::std::mem::size_of::<ServoBundledURI>() , 40usize , concat
+        assert_eq!(::std::mem::size_of::<ServoBundledURI>() , 24usize , concat
                    ! ( "Size of: " , stringify ! ( ServoBundledURI ) ));
         assert_eq! (::std::mem::align_of::<ServoBundledURI>() , 8usize ,
                     concat ! (
@@ -26740,59 +26764,15 @@ pub mod root {
                     "Alignment of field: " , stringify ! ( ServoBundledURI ) ,
                     "::" , stringify ! ( mURLStringLength ) ));
         assert_eq! (unsafe {
-                    & ( * ( 0 as * const ServoBundledURI ) ) . mBaseURI as *
+                    & ( * ( 0 as * const ServoBundledURI ) ) . mExtraData as *
                     const _ as usize } , 16usize , concat ! (
                     "Alignment of field: " , stringify ! ( ServoBundledURI ) ,
-                    "::" , stringify ! ( mBaseURI ) ));
-        assert_eq! (unsafe {
-                    & ( * ( 0 as * const ServoBundledURI ) ) . mReferrer as *
-                    const _ as usize } , 24usize , concat ! (
-                    "Alignment of field: " , stringify ! ( ServoBundledURI ) ,
-                    "::" , stringify ! ( mReferrer ) ));
-        assert_eq! (unsafe {
-                    & ( * ( 0 as * const ServoBundledURI ) ) . mPrincipal as *
-                    const _ as usize } , 32usize , concat ! (
-                    "Alignment of field: " , stringify ! ( ServoBundledURI ) ,
-                    "::" , stringify ! ( mPrincipal ) ));
+                    "::" , stringify ! ( mExtraData ) ));
     }
     impl Clone for ServoBundledURI {
         fn clone(&self) -> Self { *self }
     }
     #[repr(C)]
-    #[derive(Debug)]
-    pub struct GeckoParserExtraData {
-        pub mBaseURI: root::RefPtr<root::nsMainThreadPtrHolder<root::nsIURI>>,
-        pub mReferrer: root::RefPtr<root::nsMainThreadPtrHolder<root::nsIURI>>,
-        pub mPrincipal: root::RefPtr<root::nsMainThreadPtrHolder<root::nsIPrincipal>>,
-    }
-    #[test]
-    fn bindgen_test_layout_GeckoParserExtraData() {
-        assert_eq!(::std::mem::size_of::<GeckoParserExtraData>() , 24usize ,
-                   concat ! (
-                   "Size of: " , stringify ! ( GeckoParserExtraData ) ));
-        assert_eq! (::std::mem::align_of::<GeckoParserExtraData>() , 8usize ,
-                    concat ! (
-                    "Alignment of " , stringify ! ( GeckoParserExtraData ) ));
-        assert_eq! (unsafe {
-                    & ( * ( 0 as * const GeckoParserExtraData ) ) . mBaseURI
-                    as * const _ as usize } , 0usize , concat ! (
-                    "Alignment of field: " , stringify ! (
-                    GeckoParserExtraData ) , "::" , stringify ! ( mBaseURI )
-                    ));
-        assert_eq! (unsafe {
-                    & ( * ( 0 as * const GeckoParserExtraData ) ) . mReferrer
-                    as * const _ as usize } , 8usize , concat ! (
-                    "Alignment of field: " , stringify ! (
-                    GeckoParserExtraData ) , "::" , stringify ! ( mReferrer )
-                    ));
-        assert_eq! (unsafe {
-                    & ( * ( 0 as * const GeckoParserExtraData ) ) . mPrincipal
-                    as * const _ as usize } , 16usize , concat ! (
-                    "Alignment of field: " , stringify ! (
-                    GeckoParserExtraData ) , "::" , stringify ! ( mPrincipal )
-                    ));
-    }
-    #[repr(C)]
     #[derive(Debug, Copy, Clone)]
     pub struct nsROCSSPrimitiveValue([u8; 0]);
     #[repr(C)]
@@ -27969,54 +27949,30 @@ pub mod root {
     }
     #[test]
     fn __bindgen_test_layout_template_75() {
-        assert_eq!(::std::mem::size_of::<root::nsMainThreadPtrHolder<root::nsIURI>>()
-                   , 24usize , concat ! (
-                   "Size of template specialization: " , stringify ! (
-                   root::nsMainThreadPtrHolder<root::nsIURI> ) ));
-        assert_eq!(::std::mem::align_of::<root::nsMainThreadPtrHolder<root::nsIURI>>()
-                   , 8usize , concat ! (
-                   "Alignment of template specialization: " , stringify ! (
-                   root::nsMainThreadPtrHolder<root::nsIURI> ) ));
-    }
-    #[test]
-    fn __bindgen_test_layout_template_76() {
-        assert_eq!(::std::mem::size_of::<root::already_AddRefed<root::nsMainThreadPtrHolder<root::nsIURI>>>()
+        assert_eq!(::std::mem::size_of::<root::already_AddRefed<root::mozilla::css::URLExtraData>>()
                    , 8usize , concat ! (
                    "Size of template specialization: " , stringify ! (
-                   root::already_AddRefed<root::nsMainThreadPtrHolder<root::nsIURI>>
-                   ) ));
-        assert_eq!(::std::mem::align_of::<root::already_AddRefed<root::nsMainThreadPtrHolder<root::nsIURI>>>()
+                   root::already_AddRefed<root::mozilla::css::URLExtraData> )
+                   ));
+        assert_eq!(::std::mem::align_of::<root::already_AddRefed<root::mozilla::css::URLExtraData>>()
                    , 8usize , concat ! (
                    "Alignment of template specialization: " , stringify ! (
-                   root::already_AddRefed<root::nsMainThreadPtrHolder<root::nsIURI>>
-                   ) ));
+                   root::already_AddRefed<root::mozilla::css::URLExtraData> )
+                   ));
     }
     #[test]
-    fn __bindgen_test_layout_template_77() {
-        assert_eq!(::std::mem::size_of::<root::nsMainThreadPtrHolder<root::nsIPrincipal>>()
+    fn __bindgen_test_layout_template_76() {
+        assert_eq!(::std::mem::size_of::<root::nsMainThreadPtrHolder<root::nsIURI>>()
                    , 24usize , concat ! (
                    "Size of template specialization: " , stringify ! (
-                   root::nsMainThreadPtrHolder<root::nsIPrincipal> ) ));
-        assert_eq!(::std::mem::align_of::<root::nsMainThreadPtrHolder<root::nsIPrincipal>>()
-                   , 8usize , concat ! (
-                   "Alignment of template specialization: " , stringify ! (
-                   root::nsMainThreadPtrHolder<root::nsIPrincipal> ) ));
-    }
-    #[test]
-    fn __bindgen_test_layout_template_78() {
-        assert_eq!(::std::mem::size_of::<root::already_AddRefed<root::nsMainThreadPtrHolder<root::nsIPrincipal>>>()
-                   , 8usize , concat ! (
-                   "Size of template specialization: " , stringify ! (
-                   root::already_AddRefed<root::nsMainThreadPtrHolder<root::nsIPrincipal>>
-                   ) ));
-        assert_eq!(::std::mem::align_of::<root::already_AddRefed<root::nsMainThreadPtrHolder<root::nsIPrincipal>>>()
+                   root::nsMainThreadPtrHolder<root::nsIURI> ) ));
+        assert_eq!(::std::mem::align_of::<root::nsMainThreadPtrHolder<root::nsIURI>>()
                    , 8usize , concat ! (
                    "Alignment of template specialization: " , stringify ! (
-                   root::already_AddRefed<root::nsMainThreadPtrHolder<root::nsIPrincipal>>
-                   ) ));
+                   root::nsMainThreadPtrHolder<root::nsIURI> ) ));
     }
     #[test]
-    fn __bindgen_test_layout_template_79() {
+    fn __bindgen_test_layout_template_77() {
         assert_eq!(::std::mem::size_of::<root::mozilla::DefaultDelete<root::nsCSSValueList>>()
                    , 1usize , concat ! (
                    "Size of template specialization: " , stringify ! (
@@ -28027,7 +27983,7 @@ pub mod root {
                    root::mozilla::DefaultDelete<root::nsCSSValueList> ) ));
     }
     #[test]
-    fn __bindgen_test_layout_template_80() {
+    fn __bindgen_test_layout_template_78() {
         assert_eq!(::std::mem::size_of::<root::mozilla::UniquePtr<root::nsCSSValueList,
                                                root::mozilla::DefaultDelete<root::nsCSSValueList>>>()
                    , 8usize , concat ! (
@@ -28044,7 +28000,7 @@ pub mod root {
                    ) ));
     }
     #[test]
-    fn __bindgen_test_layout_template_81() {
+    fn __bindgen_test_layout_template_79() {
         assert_eq!(::std::mem::size_of::<root::mozilla::DefaultDelete<root::nsCSSValuePairList>>()
                    , 1usize , concat ! (
                    "Size of template specialization: " , stringify ! (
@@ -28057,7 +28013,7 @@ pub mod root {
                    ));
     }
     #[test]
-    fn __bindgen_test_layout_template_82() {
+    fn __bindgen_test_layout_template_80() {
         assert_eq!(::std::mem::size_of::<root::mozilla::UniquePtr<root::nsCSSValuePairList,
                                                root::mozilla::DefaultDelete<root::nsCSSValuePairList>>>()
                    , 8usize , concat ! (
@@ -28074,7 +28030,7 @@ pub mod root {
                    ) ));
     }
     #[test]
-    fn __bindgen_test_layout_template_83() {
+    fn __bindgen_test_layout_template_81() {
         assert_eq!(::std::mem::size_of::<root::nsTArray<root::mozilla::FramePropertyTable_PropertyValue>>()
                    , 8usize , concat ! (
                    "Size of template specialization: " , stringify ! (
@@ -28087,7 +28043,7 @@ pub mod root {
                    ) ));
     }
     #[test]
-    fn __bindgen_test_layout_template_84() {
+    fn __bindgen_test_layout_template_82() {
         assert_eq!(::std::mem::size_of::<root::nsPtrHashKey<root::nsIFrame>>()
                    , 16usize , concat ! (
                    "Size of template specialization: " , stringify ! (
@@ -28098,7 +28054,7 @@ pub mod root {
                    root::nsPtrHashKey<root::nsIFrame> ) ));
     }
     #[test]
-    fn __bindgen_test_layout_template_85() {
+    fn __bindgen_test_layout_template_83() {
         assert_eq!(::std::mem::size_of::<[u64; 6usize]>() , 48usize , concat !
                    (
                    "Size of template specialization: " , stringify ! (
@@ -28109,7 +28065,7 @@ pub mod root {
                    [u64; 6usize] ) ));
     }
     #[test]
-    fn __bindgen_test_layout_template_86() {
+    fn __bindgen_test_layout_template_84() {
         assert_eq!(::std::mem::size_of::<root::mozilla::OwningNonNull<root::mozilla::EffectCompositor_AnimationStyleRuleProcessor>>()
                    , 16usize , concat ! (
                    "Size of template specialization: " , stringify ! (
@@ -28122,7 +28078,7 @@ pub mod root {
                    ) ));
     }
     #[test]
-    fn __bindgen_test_layout_template_87() {
+    fn __bindgen_test_layout_template_85() {
         assert_eq!(::std::mem::size_of::<[u64; 2usize]>() , 16usize , concat !
                    (
                    "Size of template specialization: " , stringify ! (
@@ -28133,7 +28089,7 @@ pub mod root {
                    [u64; 2usize] ) ));
     }
     #[test]
-    fn __bindgen_test_layout_template_88() {
+    fn __bindgen_test_layout_template_86() {
         assert_eq!(::std::mem::size_of::<u64>() , 8usize , concat ! (
                    "Size of template specialization: " , stringify ! ( u64 )
                    ));
@@ -28142,7 +28098,7 @@ pub mod root {
                    u64 ) ));
     }
     #[test]
-    fn __bindgen_test_layout_template_89() {
+    fn __bindgen_test_layout_template_87() {
         assert_eq!(::std::mem::size_of::<[u32; 3usize]>() , 12usize , concat !
                    (
                    "Size of template specialization: " , stringify ! (
@@ -28153,7 +28109,7 @@ pub mod root {
                    [u32; 3usize] ) ));
     }
     #[test]
-    fn __bindgen_test_layout_template_90() {
+    fn __bindgen_test_layout_template_88() {
         assert_eq!(::std::mem::size_of::<root::already_AddRefed<root::nsStyleImageRequest>>()
                    , 8usize , concat ! (
                    "Size of template specialization: " , stringify ! (
@@ -28164,7 +28120,7 @@ pub mod root {
                    root::already_AddRefed<root::nsStyleImageRequest> ) ));
     }
     #[test]
-    fn __bindgen_test_layout_template_91() {
+    fn __bindgen_test_layout_template_89() {
         assert_eq!(::std::mem::size_of::<root::mozilla::DefaultDelete<root::nsStyleSides>>()
                    , 1usize , concat ! (
                    "Size of template specialization: " , stringify ! (
@@ -28175,7 +28131,7 @@ pub mod root {
                    root::mozilla::DefaultDelete<root::nsStyleSides> ) ));
     }
     #[test]
-    fn __bindgen_test_layout_template_92() {
+    fn __bindgen_test_layout_template_90() {
         assert_eq!(::std::mem::size_of::<root::mozilla::UniquePtr<root::nsStyleSides,
                                                root::mozilla::DefaultDelete<root::nsStyleSides>>>()
                    , 8usize , concat ! (
@@ -28192,7 +28148,7 @@ pub mod root {
                    ) ));
     }
     #[test]
-    fn __bindgen_test_layout_template_93() {
+    fn __bindgen_test_layout_template_91() {
         assert_eq!(::std::mem::size_of::<root::mozilla::DefaultDelete<root::CachedBorderImageData>>()
                    , 1usize , concat ! (
                    "Size of template specialization: " , stringify ! (
@@ -28205,7 +28161,7 @@ pub mod root {
                    ));
     }
     #[test]
-    fn __bindgen_test_layout_template_94() {
+    fn __bindgen_test_layout_template_92() {
         assert_eq!(::std::mem::size_of::<root::std::pair<::nsstring::nsStringRepr, ::nsstring::nsStringRepr>>()
                    , 32usize , concat ! (
                    "Size of template specialization: " , stringify ! (
@@ -28216,7 +28172,7 @@ pub mod root {
                    root::std::pair<::nsstring::nsStringRepr, ::nsstring::nsStringRepr> ) ));
     }
     #[test]
-    fn __bindgen_test_layout_template_95() {
+    fn __bindgen_test_layout_template_93() {
         assert_eq!(::std::mem::size_of::<root::nsTArray<root::std::pair<::nsstring::nsStringRepr,
                                                      ::nsstring::nsStringRepr>>>()
                    , 8usize , concat ! (
@@ -28231,7 +28187,7 @@ pub mod root {
                    ) ));
     }
     #[test]
-    fn __bindgen_test_layout_template_96() {
+    fn __bindgen_test_layout_template_94() {
         assert_eq!(::std::mem::size_of::<[u64; 18usize]>() , 144usize , concat
                    ! (
                    "Size of template specialization: " , stringify ! (
@@ -28242,7 +28198,7 @@ pub mod root {
                    [u64; 18usize] ) ));
     }
     #[test]
-    fn __bindgen_test_layout_template_97() {
+    fn __bindgen_test_layout_template_95() {
         assert_eq!(::std::mem::size_of::<root::nsTArray<root::mozilla::DisplayItemClip_RoundedRect>>()
                    , 8usize , concat ! (
                    "Size of template specialization: " , stringify ! (
@@ -28255,7 +28211,7 @@ pub mod root {
                    ) ));
     }
     #[test]
-    fn __bindgen_test_layout_template_98() {
+    fn __bindgen_test_layout_template_96() {
         assert_eq!(::std::mem::size_of::<root::RefPtr<root::mozilla::dom::DOMRect>>()
                    , 8usize , concat ! (
                    "Size of template specialization: " , stringify ! (
@@ -28266,7 +28222,7 @@ pub mod root {
                    root::RefPtr<root::mozilla::dom::DOMRect> ) ));
     }
     #[test]
-    fn __bindgen_test_layout_template_99() {
+    fn __bindgen_test_layout_template_97() {
         assert_eq!(::std::mem::size_of::<u64>() , 8usize , concat ! (
                    "Size of template specialization: " , stringify ! ( u64 )
                    ));
@@ -28275,7 +28231,7 @@ pub mod root {
                    u64 ) ));
     }
     #[test]
-    fn __bindgen_test_layout_template_100() {
+    fn __bindgen_test_layout_template_98() {
         assert_eq!(::std::mem::size_of::<root::nsTArray<*mut root::mozilla::css::DocumentRule>>()
                    , 8usize , concat ! (
                    "Size of template specialization: " , stringify ! (
@@ -28286,7 +28242,7 @@ pub mod root {
                    root::nsTArray<*mut root::mozilla::css::DocumentRule> ) ));
     }
     #[test]
-    fn __bindgen_test_layout_template_101() {
+    fn __bindgen_test_layout_template_99() {
         assert_eq!(::std::mem::size_of::<root::nsAutoPtr<root::nsMediaQuery>>()
                    , 8usize , concat ! (
                    "Size of template specialization: " , stringify ! (
diff --git a/components/style/gecko_bindings/structs_release.rs b/components/style/gecko_bindings/structs_release.rs
index fa6cdd8a419..8442777cbcc 100644
--- a/components/style/gecko_bindings/structs_release.rs
+++ b/components/style/gecko_bindings/structs_release.rs
@@ -5163,6 +5163,49 @@ pub mod root {
             #[derive(Debug, Copy, Clone)]
             pub struct ImageLoader([u8; 0]);
             #[repr(C)]
+            #[derive(Debug)]
+            pub struct URLExtraData {
+                pub mRefCnt: root::mozilla::ThreadSafeAutoRefCnt,
+                pub mBaseURI: root::RefPtr<root::nsIURI>,
+                pub mReferrer: root::RefPtr<root::nsIURI>,
+                pub mPrincipal: root::RefPtr<root::nsIPrincipal>,
+            }
+            pub type URLExtraData_HasThreadSafeRefCnt =
+                root::mozilla::TrueType;
+            #[test]
+            fn bindgen_test_layout_URLExtraData() {
+                assert_eq!(::std::mem::size_of::<URLExtraData>() , 32usize ,
+                           concat ! (
+                           "Size of: " , stringify ! ( URLExtraData ) ));
+                assert_eq! (::std::mem::align_of::<URLExtraData>() , 8usize ,
+                            concat ! (
+                            "Alignment of " , stringify ! ( URLExtraData ) ));
+                assert_eq! (unsafe {
+                            & ( * ( 0 as * const URLExtraData ) ) . mRefCnt as
+                            * const _ as usize } , 0usize , concat ! (
+                            "Alignment of field: " , stringify ! (
+                            URLExtraData ) , "::" , stringify ! ( mRefCnt )
+                            ));
+                assert_eq! (unsafe {
+                            & ( * ( 0 as * const URLExtraData ) ) . mBaseURI
+                            as * const _ as usize } , 8usize , concat ! (
+                            "Alignment of field: " , stringify ! (
+                            URLExtraData ) , "::" , stringify ! ( mBaseURI )
+                            ));
+                assert_eq! (unsafe {
+                            & ( * ( 0 as * const URLExtraData ) ) . mReferrer
+                            as * const _ as usize } , 16usize , concat ! (
+                            "Alignment of field: " , stringify ! (
+                            URLExtraData ) , "::" , stringify ! ( mReferrer )
+                            ));
+                assert_eq! (unsafe {
+                            & ( * ( 0 as * const URLExtraData ) ) . mPrincipal
+                            as * const _ as usize } , 24usize , concat ! (
+                            "Alignment of field: " , stringify ! (
+                            URLExtraData ) , "::" , stringify ! ( mPrincipal )
+                            ));
+            }
+            #[repr(C)]
             pub struct URLValueData__bindgen_vtable {
             }
             #[repr(C)]
@@ -5171,10 +5214,8 @@ pub mod root {
                 pub vtable_: *const URLValueData__bindgen_vtable,
                 pub mRefCnt: root::mozilla::ThreadSafeAutoRefCnt,
                 pub mURI: root::nsMainThreadPtrHandle<root::nsIURI>,
-                pub mBaseURI: root::nsMainThreadPtrHandle<root::nsIURI>,
                 pub mString: root::RefPtr<root::nsStringBuffer>,
-                pub mReferrer: root::nsMainThreadPtrHandle<root::nsIURI>,
-                pub mOriginPrincipal: root::nsMainThreadPtrHandle<root::nsIPrincipal>,
+                pub mExtraData: root::RefPtr<root::mozilla::css::URLExtraData>,
                 pub mURIResolved: bool,
                 pub mIsLocalRef: bool,
             }
@@ -5182,7 +5223,7 @@ pub mod root {
                 root::mozilla::TrueType;
             #[test]
             fn bindgen_test_layout_URLValueData() {
-                assert_eq!(::std::mem::size_of::<URLValueData>() , 64usize ,
+                assert_eq!(::std::mem::size_of::<URLValueData>() , 48usize ,
                            concat ! (
                            "Size of: " , stringify ! ( URLValueData ) ));
                 assert_eq! (::std::mem::align_of::<URLValueData>() , 8usize ,
@@ -5200,40 +5241,27 @@ pub mod root {
                             "Alignment of field: " , stringify ! (
                             URLValueData ) , "::" , stringify ! ( mURI ) ));
                 assert_eq! (unsafe {
-                            & ( * ( 0 as * const URLValueData ) ) . mBaseURI
-                            as * const _ as usize } , 24usize , concat ! (
-                            "Alignment of field: " , stringify ! (
-                            URLValueData ) , "::" , stringify ! ( mBaseURI )
-                            ));
-                assert_eq! (unsafe {
                             & ( * ( 0 as * const URLValueData ) ) . mString as
-                            * const _ as usize } , 32usize , concat ! (
+                            * const _ as usize } , 24usize , concat ! (
                             "Alignment of field: " , stringify ! (
                             URLValueData ) , "::" , stringify ! ( mString )
                             ));
                 assert_eq! (unsafe {
-                            & ( * ( 0 as * const URLValueData ) ) . mReferrer
-                            as * const _ as usize } , 40usize , concat ! (
+                            & ( * ( 0 as * const URLValueData ) ) . mExtraData
+                            as * const _ as usize } , 32usize , concat ! (
                             "Alignment of field: " , stringify ! (
-                            URLValueData ) , "::" , stringify ! ( mReferrer )
+                            URLValueData ) , "::" , stringify ! ( mExtraData )
                             ));
                 assert_eq! (unsafe {
                             & ( * ( 0 as * const URLValueData ) ) .
-                            mOriginPrincipal as * const _ as usize } , 48usize
-                            , concat ! (
-                            "Alignment of field: " , stringify ! (
-                            URLValueData ) , "::" , stringify ! (
-                            mOriginPrincipal ) ));
-                assert_eq! (unsafe {
-                            & ( * ( 0 as * const URLValueData ) ) .
-                            mURIResolved as * const _ as usize } , 56usize ,
+                            mURIResolved as * const _ as usize } , 40usize ,
                             concat ! (
                             "Alignment of field: " , stringify ! (
                             URLValueData ) , "::" , stringify ! ( mURIResolved
                             ) ));
                 assert_eq! (unsafe {
                             & ( * ( 0 as * const URLValueData ) ) .
-                            mIsLocalRef as * const _ as usize } , 57usize ,
+                            mIsLocalRef as * const _ as usize } , 41usize ,
                             concat ! (
                             "Alignment of field: " , stringify ! (
                             URLValueData ) , "::" , stringify ! ( mIsLocalRef
@@ -5246,7 +5274,7 @@ pub mod root {
             }
             #[test]
             fn bindgen_test_layout_URLValue() {
-                assert_eq!(::std::mem::size_of::<URLValue>() , 64usize ,
+                assert_eq!(::std::mem::size_of::<URLValue>() , 48usize ,
                            concat ! ( "Size of: " , stringify ! ( URLValue )
                            ));
                 assert_eq! (::std::mem::align_of::<URLValue>() , 8usize ,
@@ -5261,7 +5289,7 @@ pub mod root {
             }
             #[test]
             fn bindgen_test_layout_ImageValue() {
-                assert_eq!(::std::mem::size_of::<ImageValue>() , 104usize ,
+                assert_eq!(::std::mem::size_of::<ImageValue>() , 88usize ,
                            concat ! ( "Size of: " , stringify ! ( ImageValue )
                            ));
                 assert_eq! (::std::mem::align_of::<ImageValue>() , 8usize ,
@@ -5269,7 +5297,7 @@ pub mod root {
                             "Alignment of " , stringify ! ( ImageValue ) ));
                 assert_eq! (unsafe {
                             & ( * ( 0 as * const ImageValue ) ) . mRequests as
-                            * const _ as usize } , 64usize , concat ! (
+                            * const _ as usize } , 48usize , concat ! (
                             "Alignment of field: " , stringify ! ( ImageValue
                             ) , "::" , stringify ! ( mRequests ) ));
             }
@@ -25827,6 +25855,7 @@ pub mod root {
     pub type RawGeckoElement = root::mozilla::dom::Element;
     pub type RawGeckoDocument = root::nsIDocument;
     pub type RawGeckoPresContext = root::nsPresContext;
+    pub type RawGeckoURLExtraData = root::mozilla::css::URLExtraData;
     pub type RawGeckoKeyframeList = root::nsTArray<root::mozilla::Keyframe>;
     pub type RawGeckoComputedKeyframeValuesList =
         root::nsTArray<root::nsTArray<root::mozilla::PropertyStyleAnimationValuePair>>;
@@ -26070,21 +26099,16 @@ pub mod root {
     impl Clone for nsMediaFeature {
         fn clone(&self) -> Self { *self }
     }
-    pub type ThreadSafePrincipalHolder =
-        root::nsMainThreadPtrHolder<root::nsIPrincipal>;
-    pub type ThreadSafeURIHolder = root::nsMainThreadPtrHolder<root::nsIURI>;
     #[repr(C)]
     #[derive(Debug, Copy)]
     pub struct ServoBundledURI {
         pub mURLString: *const u8,
         pub mURLStringLength: u32,
-        pub mBaseURI: *mut root::ThreadSafeURIHolder,
-        pub mReferrer: *mut root::ThreadSafeURIHolder,
-        pub mPrincipal: *mut root::ThreadSafePrincipalHolder,
+        pub mExtraData: *mut root::mozilla::css::URLExtraData,
     }
     #[test]
     fn bindgen_test_layout_ServoBundledURI() {
-        assert_eq!(::std::mem::size_of::<ServoBundledURI>() , 40usize , concat
+        assert_eq!(::std::mem::size_of::<ServoBundledURI>() , 24usize , concat
                    ! ( "Size of: " , stringify ! ( ServoBundledURI ) ));
         assert_eq! (::std::mem::align_of::<ServoBundledURI>() , 8usize ,
                     concat ! (
@@ -26101,59 +26125,15 @@ pub mod root {
                     "Alignment of field: " , stringify ! ( ServoBundledURI ) ,
                     "::" , stringify ! ( mURLStringLength ) ));
         assert_eq! (unsafe {
-                    & ( * ( 0 as * const ServoBundledURI ) ) . mBaseURI as *
+                    & ( * ( 0 as * const ServoBundledURI ) ) . mExtraData as *
                     const _ as usize } , 16usize , concat ! (
                     "Alignment of field: " , stringify ! ( ServoBundledURI ) ,
-                    "::" , stringify ! ( mBaseURI ) ));
-        assert_eq! (unsafe {
-                    & ( * ( 0 as * const ServoBundledURI ) ) . mReferrer as *
-                    const _ as usize } , 24usize , concat ! (
-                    "Alignment of field: " , stringify ! ( ServoBundledURI ) ,
-                    "::" , stringify ! ( mReferrer ) ));
-        assert_eq! (unsafe {
-                    & ( * ( 0 as * const ServoBundledURI ) ) . mPrincipal as *
-                    const _ as usize } , 32usize , concat ! (
-                    "Alignment of field: " , stringify ! ( ServoBundledURI ) ,
-                    "::" , stringify ! ( mPrincipal ) ));
+                    "::" , stringify ! ( mExtraData ) ));
     }
     impl Clone for ServoBundledURI {
         fn clone(&self) -> Self { *self }
     }
     #[repr(C)]
-    #[derive(Debug)]
-    pub struct GeckoParserExtraData {
-        pub mBaseURI: root::RefPtr<root::nsMainThreadPtrHolder<root::nsIURI>>,
-        pub mReferrer: root::RefPtr<root::nsMainThreadPtrHolder<root::nsIURI>>,
-        pub mPrincipal: root::RefPtr<root::nsMainThreadPtrHolder<root::nsIPrincipal>>,
-    }
-    #[test]
-    fn bindgen_test_layout_GeckoParserExtraData() {
-        assert_eq!(::std::mem::size_of::<GeckoParserExtraData>() , 24usize ,
-                   concat ! (
-                   "Size of: " , stringify ! ( GeckoParserExtraData ) ));
-        assert_eq! (::std::mem::align_of::<GeckoParserExtraData>() , 8usize ,
-                    concat ! (
-                    "Alignment of " , stringify ! ( GeckoParserExtraData ) ));
-        assert_eq! (unsafe {
-                    & ( * ( 0 as * const GeckoParserExtraData ) ) . mBaseURI
-                    as * const _ as usize } , 0usize , concat ! (
-                    "Alignment of field: " , stringify ! (
-                    GeckoParserExtraData ) , "::" , stringify ! ( mBaseURI )
-                    ));
-        assert_eq! (unsafe {
-                    & ( * ( 0 as * const GeckoParserExtraData ) ) . mReferrer
-                    as * const _ as usize } , 8usize , concat ! (
-                    "Alignment of field: " , stringify ! (
-                    GeckoParserExtraData ) , "::" , stringify ! ( mReferrer )
-                    ));
-        assert_eq! (unsafe {
-                    & ( * ( 0 as * const GeckoParserExtraData ) ) . mPrincipal
-                    as * const _ as usize } , 16usize , concat ! (
-                    "Alignment of field: " , stringify ! (
-                    GeckoParserExtraData ) , "::" , stringify ! ( mPrincipal )
-                    ));
-    }
-    #[repr(C)]
     #[derive(Debug, Copy, Clone)]
     pub struct nsROCSSPrimitiveValue([u8; 0]);
     #[repr(C)]
@@ -27330,54 +27310,30 @@ pub mod root {
     }
     #[test]
     fn __bindgen_test_layout_template_75() {
-        assert_eq!(::std::mem::size_of::<root::nsMainThreadPtrHolder<root::nsIURI>>()
-                   , 24usize , concat ! (
-                   "Size of template specialization: " , stringify ! (
-                   root::nsMainThreadPtrHolder<root::nsIURI> ) ));
-        assert_eq!(::std::mem::align_of::<root::nsMainThreadPtrHolder<root::nsIURI>>()
-                   , 8usize , concat ! (
-                   "Alignment of template specialization: " , stringify ! (
-                   root::nsMainThreadPtrHolder<root::nsIURI> ) ));
-    }
-    #[test]
-    fn __bindgen_test_layout_template_76() {
-        assert_eq!(::std::mem::size_of::<root::already_AddRefed<root::nsMainThreadPtrHolder<root::nsIURI>>>()
+        assert_eq!(::std::mem::size_of::<root::already_AddRefed<root::mozilla::css::URLExtraData>>()
                    , 8usize , concat ! (
                    "Size of template specialization: " , stringify ! (
-                   root::already_AddRefed<root::nsMainThreadPtrHolder<root::nsIURI>>
-                   ) ));
-        assert_eq!(::std::mem::align_of::<root::already_AddRefed<root::nsMainThreadPtrHolder<root::nsIURI>>>()
+                   root::already_AddRefed<root::mozilla::css::URLExtraData> )
+                   ));
+        assert_eq!(::std::mem::align_of::<root::already_AddRefed<root::mozilla::css::URLExtraData>>()
                    , 8usize , concat ! (
                    "Alignment of template specialization: " , stringify ! (
-                   root::already_AddRefed<root::nsMainThreadPtrHolder<root::nsIURI>>
-                   ) ));
+                   root::already_AddRefed<root::mozilla::css::URLExtraData> )
+                   ));
     }
     #[test]
-    fn __bindgen_test_layout_template_77() {
-        assert_eq!(::std::mem::size_of::<root::nsMainThreadPtrHolder<root::nsIPrincipal>>()
+    fn __bindgen_test_layout_template_76() {
+        assert_eq!(::std::mem::size_of::<root::nsMainThreadPtrHolder<root::nsIURI>>()
                    , 24usize , concat ! (
                    "Size of template specialization: " , stringify ! (
-                   root::nsMainThreadPtrHolder<root::nsIPrincipal> ) ));
-        assert_eq!(::std::mem::align_of::<root::nsMainThreadPtrHolder<root::nsIPrincipal>>()
-                   , 8usize , concat ! (
-                   "Alignment of template specialization: " , stringify ! (
-                   root::nsMainThreadPtrHolder<root::nsIPrincipal> ) ));
-    }
-    #[test]
-    fn __bindgen_test_layout_template_78() {
-        assert_eq!(::std::mem::size_of::<root::already_AddRefed<root::nsMainThreadPtrHolder<root::nsIPrincipal>>>()
-                   , 8usize , concat ! (
-                   "Size of template specialization: " , stringify ! (
-                   root::already_AddRefed<root::nsMainThreadPtrHolder<root::nsIPrincipal>>
-                   ) ));
-        assert_eq!(::std::mem::align_of::<root::already_AddRefed<root::nsMainThreadPtrHolder<root::nsIPrincipal>>>()
+                   root::nsMainThreadPtrHolder<root::nsIURI> ) ));
+        assert_eq!(::std::mem::align_of::<root::nsMainThreadPtrHolder<root::nsIURI>>()
                    , 8usize , concat ! (
                    "Alignment of template specialization: " , stringify ! (
-                   root::already_AddRefed<root::nsMainThreadPtrHolder<root::nsIPrincipal>>
-                   ) ));
+                   root::nsMainThreadPtrHolder<root::nsIURI> ) ));
     }
     #[test]
-    fn __bindgen_test_layout_template_79() {
+    fn __bindgen_test_layout_template_77() {
         assert_eq!(::std::mem::size_of::<root::mozilla::DefaultDelete<root::nsCSSValueList>>()
                    , 1usize , concat ! (
                    "Size of template specialization: " , stringify ! (
@@ -27388,7 +27344,7 @@ pub mod root {
                    root::mozilla::DefaultDelete<root::nsCSSValueList> ) ));
     }
     #[test]
-    fn __bindgen_test_layout_template_80() {
+    fn __bindgen_test_layout_template_78() {
         assert_eq!(::std::mem::size_of::<root::mozilla::UniquePtr<root::nsCSSValueList,
                                                root::mozilla::DefaultDelete<root::nsCSSValueList>>>()
                    , 8usize , concat ! (
@@ -27405,7 +27361,7 @@ pub mod root {
                    ) ));
     }
     #[test]
-    fn __bindgen_test_layout_template_81() {
+    fn __bindgen_test_layout_template_79() {
         assert_eq!(::std::mem::size_of::<root::mozilla::DefaultDelete<root::nsCSSValuePairList>>()
                    , 1usize , concat ! (
                    "Size of template specialization: " , stringify ! (
@@ -27418,7 +27374,7 @@ pub mod root {
                    ));
     }
     #[test]
-    fn __bindgen_test_layout_template_82() {
+    fn __bindgen_test_layout_template_80() {
         assert_eq!(::std::mem::size_of::<root::mozilla::UniquePtr<root::nsCSSValuePairList,
                                                root::mozilla::DefaultDelete<root::nsCSSValuePairList>>>()
                    , 8usize , concat ! (
@@ -27435,7 +27391,7 @@ pub mod root {
                    ) ));
     }
     #[test]
-    fn __bindgen_test_layout_template_83() {
+    fn __bindgen_test_layout_template_81() {
         assert_eq!(::std::mem::size_of::<root::nsTArray<root::mozilla::FramePropertyTable_PropertyValue>>()
                    , 8usize , concat ! (
                    "Size of template specialization: " , stringify ! (
@@ -27448,7 +27404,7 @@ pub mod root {
                    ) ));
     }
     #[test]
-    fn __bindgen_test_layout_template_84() {
+    fn __bindgen_test_layout_template_82() {
         assert_eq!(::std::mem::size_of::<root::nsPtrHashKey<root::nsIFrame>>()
                    , 16usize , concat ! (
                    "Size of template specialization: " , stringify ! (
@@ -27459,7 +27415,7 @@ pub mod root {
                    root::nsPtrHashKey<root::nsIFrame> ) ));
     }
     #[test]
-    fn __bindgen_test_layout_template_85() {
+    fn __bindgen_test_layout_template_83() {
         assert_eq!(::std::mem::size_of::<[u64; 5usize]>() , 40usize , concat !
                    (
                    "Size of template specialization: " , stringify ! (
@@ -27470,7 +27426,7 @@ pub mod root {
                    [u64; 5usize] ) ));
     }
     #[test]
-    fn __bindgen_test_layout_template_86() {
+    fn __bindgen_test_layout_template_84() {
         assert_eq!(::std::mem::size_of::<root::mozilla::OwningNonNull<root::mozilla::EffectCompositor_AnimationStyleRuleProcessor>>()
                    , 8usize , concat ! (
                    "Size of template specialization: " , stringify ! (
@@ -27483,7 +27439,7 @@ pub mod root {
                    ) ));
     }
     #[test]
-    fn __bindgen_test_layout_template_87() {
+    fn __bindgen_test_layout_template_85() {
         assert_eq!(::std::mem::size_of::<[u64; 2usize]>() , 16usize , concat !
                    (
                    "Size of template specialization: " , stringify ! (
@@ -27494,7 +27450,7 @@ pub mod root {
                    [u64; 2usize] ) ));
     }
     #[test]
-    fn __bindgen_test_layout_template_88() {
+    fn __bindgen_test_layout_template_86() {
         assert_eq!(::std::mem::size_of::<u64>() , 8usize , concat ! (
                    "Size of template specialization: " , stringify ! ( u64 )
                    ));
@@ -27503,7 +27459,7 @@ pub mod root {
                    u64 ) ));
     }
     #[test]
-    fn __bindgen_test_layout_template_89() {
+    fn __bindgen_test_layout_template_87() {
         assert_eq!(::std::mem::size_of::<[u32; 3usize]>() , 12usize , concat !
                    (
                    "Size of template specialization: " , stringify ! (
@@ -27514,7 +27470,7 @@ pub mod root {
                    [u32; 3usize] ) ));
     }
     #[test]
-    fn __bindgen_test_layout_template_90() {
+    fn __bindgen_test_layout_template_88() {
         assert_eq!(::std::mem::size_of::<root::already_AddRefed<root::nsStyleImageRequest>>()
                    , 8usize , concat ! (
                    "Size of template specialization: " , stringify ! (
@@ -27525,7 +27481,7 @@ pub mod root {
                    root::already_AddRefed<root::nsStyleImageRequest> ) ));
     }
     #[test]
-    fn __bindgen_test_layout_template_91() {
+    fn __bindgen_test_layout_template_89() {
         assert_eq!(::std::mem::size_of::<root::mozilla::DefaultDelete<root::nsStyleSides>>()
                    , 1usize , concat ! (
                    "Size of template specialization: " , stringify ! (
@@ -27536,7 +27492,7 @@ pub mod root {
                    root::mozilla::DefaultDelete<root::nsStyleSides> ) ));
     }
     #[test]
-    fn __bindgen_test_layout_template_92() {
+    fn __bindgen_test_layout_template_90() {
         assert_eq!(::std::mem::size_of::<root::mozilla::UniquePtr<root::nsStyleSides,
                                                root::mozilla::DefaultDelete<root::nsStyleSides>>>()
                    , 8usize , concat ! (
@@ -27553,7 +27509,7 @@ pub mod root {
                    ) ));
     }
     #[test]
-    fn __bindgen_test_layout_template_93() {
+    fn __bindgen_test_layout_template_91() {
         assert_eq!(::std::mem::size_of::<root::mozilla::DefaultDelete<root::CachedBorderImageData>>()
                    , 1usize , concat ! (
                    "Size of template specialization: " , stringify ! (
@@ -27566,7 +27522,7 @@ pub mod root {
                    ));
     }
     #[test]
-    fn __bindgen_test_layout_template_94() {
+    fn __bindgen_test_layout_template_92() {
         assert_eq!(::std::mem::size_of::<root::std::pair<::nsstring::nsStringRepr, ::nsstring::nsStringRepr>>()
                    , 32usize , concat ! (
                    "Size of template specialization: " , stringify ! (
@@ -27577,7 +27533,7 @@ pub mod root {
                    root::std::pair<::nsstring::nsStringRepr, ::nsstring::nsStringRepr> ) ));
     }
     #[test]
-    fn __bindgen_test_layout_template_95() {
+    fn __bindgen_test_layout_template_93() {
         assert_eq!(::std::mem::size_of::<root::nsTArray<root::std::pair<::nsstring::nsStringRepr,
                                                      ::nsstring::nsStringRepr>>>()
                    , 8usize , concat ! (
@@ -27592,7 +27548,7 @@ pub mod root {
                    ) ));
     }
     #[test]
-    fn __bindgen_test_layout_template_96() {
+    fn __bindgen_test_layout_template_94() {
         assert_eq!(::std::mem::size_of::<[u64; 18usize]>() , 144usize , concat
                    ! (
                    "Size of template specialization: " , stringify ! (
@@ -27603,7 +27559,7 @@ pub mod root {
                    [u64; 18usize] ) ));
     }
     #[test]
-    fn __bindgen_test_layout_template_97() {
+    fn __bindgen_test_layout_template_95() {
         assert_eq!(::std::mem::size_of::<root::nsTArray<root::mozilla::DisplayItemClip_RoundedRect>>()
                    , 8usize , concat ! (
                    "Size of template specialization: " , stringify ! (
@@ -27616,7 +27572,7 @@ pub mod root {
                    ) ));
     }
     #[test]
-    fn __bindgen_test_layout_template_98() {
+    fn __bindgen_test_layout_template_96() {
         assert_eq!(::std::mem::size_of::<root::RefPtr<root::mozilla::dom::DOMRect>>()
                    , 8usize , concat ! (
                    "Size of template specialization: " , stringify ! (
@@ -27627,7 +27583,7 @@ pub mod root {
                    root::RefPtr<root::mozilla::dom::DOMRect> ) ));
     }
     #[test]
-    fn __bindgen_test_layout_template_99() {
+    fn __bindgen_test_layout_template_97() {
         assert_eq!(::std::mem::size_of::<u64>() , 8usize , concat ! (
                    "Size of template specialization: " , stringify ! ( u64 )
                    ));
@@ -27636,7 +27592,7 @@ pub mod root {
                    u64 ) ));
     }
     #[test]
-    fn __bindgen_test_layout_template_100() {
+    fn __bindgen_test_layout_template_98() {
         assert_eq!(::std::mem::size_of::<root::nsTArray<*mut root::mozilla::css::DocumentRule>>()
                    , 8usize , concat ! (
                    "Size of template specialization: " , stringify ! (
@@ -27647,7 +27603,7 @@ pub mod root {
                    root::nsTArray<*mut root::mozilla::css::DocumentRule> ) ));
     }
     #[test]
-    fn __bindgen_test_layout_template_101() {
+    fn __bindgen_test_layout_template_99() {
         assert_eq!(::std::mem::size_of::<root::nsAutoPtr<root::nsMediaQuery>>()
                    , 8usize , concat ! (
                    "Size of template specialization: " , stringify ! (
diff --git a/components/style/gecko_bindings/sugar/refptr.rs b/components/style/gecko_bindings/sugar/refptr.rs
index 5953652f3a5..3713ea09266 100644
--- a/components/style/gecko_bindings/sugar/refptr.rs
+++ b/components/style/gecko_bindings/sugar/refptr.rs
@@ -261,12 +261,9 @@ macro_rules! impl_threadsafe_refcount {
     );
 }
 
-impl_threadsafe_refcount!(::gecko_bindings::structs::ThreadSafePrincipalHolder,
-                          Gecko_AddRefPrincipalArbitraryThread,
-                          Gecko_ReleasePrincipalArbitraryThread);
-impl_threadsafe_refcount!(::gecko_bindings::structs::ThreadSafeURIHolder,
-                          Gecko_AddRefURIArbitraryThread,
-                          Gecko_ReleaseURIArbitraryThread);
+impl_threadsafe_refcount!(::gecko_bindings::structs::RawGeckoURLExtraData,
+                          Gecko_AddRefURLExtraDataArbitraryThread,
+                          Gecko_ReleaseURLExtraDataArbitraryThread);
 impl_threadsafe_refcount!(::gecko_bindings::structs::nsStyleQuoteValues,
                           Gecko_AddRefQuoteValuesArbitraryThread,
                           Gecko_ReleaseQuoteValuesArbitraryThread);
@@ -276,10 +273,3 @@ impl_threadsafe_refcount!(::gecko_bindings::structs::nsCSSValueSharedList,
 impl_threadsafe_refcount!(::gecko_bindings::structs::mozilla::css::URLValue,
                           Gecko_AddRefCSSURLValueArbitraryThread,
                           Gecko_ReleaseCSSURLValueArbitraryThread);
-/// A Gecko `ThreadSafePrincipalHolder` wrapped in a safe refcounted pointer, to
-/// use during stylesheet parsing and style computation.
-pub type GeckoArcPrincipal = RefPtr<::gecko_bindings::structs::ThreadSafePrincipalHolder>;
-
-/// A Gecko `ThreadSafeURIHolder` wrapped in a safe refcounted pointer, to use
-/// during stylesheet parsing and style computation.
-pub type GeckoArcURI = RefPtr<::gecko_bindings::structs::ThreadSafeURIHolder>;
diff --git a/components/style/parser.rs b/components/style/parser.rs
index 8a8628d2d89..f4d52ffbfdd 100644
--- a/components/style/parser.rs
+++ b/components/style/parser.rs
@@ -9,7 +9,9 @@
 use cssparser::{Parser, SourcePosition, UnicodeRange};
 use error_reporting::ParseErrorReporter;
 #[cfg(feature = "gecko")]
-use gecko_bindings::sugar::refptr::{GeckoArcPrincipal, GeckoArcURI};
+use gecko_bindings::structs::URLExtraData;
+#[cfg(feature = "gecko")]
+use gecko_bindings::sugar::refptr::RefPtr;
 use servo_url::ServoUrl;
 use style_traits::OneOrMoreCommaSeparated;
 use stylesheets::Origin;
@@ -21,12 +23,8 @@ pub struct ParserContextExtraData;
 /// Extra data that the style backend may need to parse stylesheets.
 #[cfg(feature = "gecko")]
 pub struct ParserContextExtraData {
-    /// The base URI.
-    pub base: Option<GeckoArcURI>,
-    /// The referrer URI.
-    pub referrer: Option<GeckoArcURI>,
-    /// The principal that loaded this stylesheet.
-    pub principal: Option<GeckoArcPrincipal>,
+    /// The URL extra data.
+    pub data: Option<RefPtr<URLExtraData>>,
 }
 
 #[cfg(not(feature = "gecko"))]
@@ -39,7 +37,7 @@ impl Default for ParserContextExtraData {
 #[cfg(feature = "gecko")]
 impl Default for ParserContextExtraData {
     fn default() -> Self {
-        ParserContextExtraData { base: None, referrer: None, principal: None }
+        ParserContextExtraData { data: None }
     }
 }
 
@@ -48,15 +46,10 @@ impl ParserContextExtraData {
     /// Construct from a GeckoParserExtraData
     ///
     /// GeckoParserExtraData must live longer than this call
-    pub unsafe fn new(data: *const ::gecko_bindings::structs::GeckoParserExtraData) -> Self {
-        // the to_safe calls are safe since we trust that we have references to
-        // real Gecko refptrs. The dereferencing of data is safe because this function
-        // is expected to be called with a `data` living longer than this function.
-        unsafe { ParserContextExtraData {
-            base: Some((*data).mBaseURI.to_safe()),
-            referrer: Some((*data).mReferrer.to_safe()),
-            principal: Some((*data).mPrincipal.to_safe()),
-        }}
+    pub unsafe fn new(data: *mut URLExtraData) -> Self {
+        ParserContextExtraData {
+            data: Some(RefPtr::new(data)),
+        }
     }
 }
 /// The data that the parser needs from outside in order to parse a stylesheet.
diff --git a/components/style/properties/longhand/box.mako.rs b/components/style/properties/longhand/box.mako.rs
index d05a5ed4a1e..244a0e4a186 100644
--- a/components/style/properties/longhand/box.mako.rs
+++ b/components/style/properties/longhand/box.mako.rs
@@ -2158,8 +2158,7 @@ ${helpers.predefined_type("-moz-binding", "UrlOrNone", "Either::Second(None_)",
                           animatable="False",
                           gecko_ffi_name="mBinding",
                           spec="Nonstandard (https://developer.mozilla.org/en-US/docs/Web/CSS/-moz-binding)",
-                          disable_when_testing="True",
-                          boxed=True)}
+                          disable_when_testing="True")}
 
 ${helpers.single_keyword("-moz-orient",
                           "inline block horizontal vertical",
diff --git a/components/style/properties/longhand/inherited_svg.mako.rs b/components/style/properties/longhand/inherited_svg.mako.rs
index 31d393f13fc..241a08905b4 100644
--- a/components/style/properties/longhand/inherited_svg.mako.rs
+++ b/components/style/properties/longhand/inherited_svg.mako.rs
@@ -121,19 +121,16 @@ ${helpers.single_keyword("clip-rule", "nonzero evenodd",
 
 ${helpers.predefined_type("marker-start", "UrlOrNone", "Either::Second(None_)",
                           products="gecko",
-                          boxed = product == "gecko",
                           animatable="False",
                           spec="https://www.w3.org/TR/SVG2/painting.html#VertexMarkerProperties")}
 
 ${helpers.predefined_type("marker-mid", "UrlOrNone", "Either::Second(None_)",
                           products="gecko",
-                          boxed = product == "gecko",
                           animatable="False",
                           spec="https://www.w3.org/TR/SVG2/painting.html#VertexMarkerProperties")}
 
 ${helpers.predefined_type("marker-end", "UrlOrNone", "Either::Second(None_)",
                           products="gecko",
-                          boxed = product == "gecko",
                           animatable="False",
                           spec="https://www.w3.org/TR/SVG2/painting.html#VertexMarkerProperties")}
 
diff --git a/components/style/properties/longhand/list.mako.rs b/components/style/properties/longhand/list.mako.rs
index 8049c06d05c..81ce62a32e1 100644
--- a/components/style/properties/longhand/list.mako.rs
+++ b/components/style/properties/longhand/list.mako.rs
@@ -38,7 +38,6 @@ ${helpers.single_keyword("list-style-type", """
     spec="https://drafts.csswg.org/css-lists/#propdef-list-style-type")}
 
 ${helpers.predefined_type("list-style-image", "UrlOrNone", "Either::Second(None_)",
-                          boxed = product == "gecko",
                           initial_specified_value="Either::Second(None_)", animatable=False,
                           spec="https://drafts.csswg.org/css-lists/#propdef-list-style-image")}
 
diff --git a/ports/geckolib/glue.rs b/ports/geckolib/glue.rs
index 455aaaf41d2..00580613e2d 100644
--- a/ports/geckolib/glue.rs
+++ b/ports/geckolib/glue.rs
@@ -54,16 +54,15 @@ use style::gecko_bindings::bindings::nsTimingFunctionBorrowed;
 use style::gecko_bindings::bindings::nsTimingFunctionBorrowedMut;
 use style::gecko_bindings::structs;
 use style::gecko_bindings::structs::{SheetParsingMode, nsIAtom, nsCSSPropertyID};
-use style::gecko_bindings::structs::{ThreadSafePrincipalHolder, ThreadSafeURIHolder};
 use style::gecko_bindings::structs::{nsRestyleHint, nsChangeHint, nsCSSFontFaceRule};
 use style::gecko_bindings::structs::Loader;
 use style::gecko_bindings::structs::RawGeckoPresContextOwned;
 use style::gecko_bindings::structs::ServoStyleSheet;
+use style::gecko_bindings::structs::URLExtraData;
 use style::gecko_bindings::structs::nsCSSValueSharedList;
 use style::gecko_bindings::structs::nsresult;
 use style::gecko_bindings::sugar::ownership::{FFIArcHelpers, HasFFI, HasArcFFI, HasBoxFFI};
 use style::gecko_bindings::sugar::ownership::{HasSimpleFFI, Strong};
-use style::gecko_bindings::sugar::refptr::{GeckoArcPrincipal, GeckoArcURI};
 use style::gecko_properties::{self, style_structs};
 use style::keyframes::KeyframesStepValue;
 use style::media_queries::{MediaList, parse_media_query_list};
@@ -331,9 +330,7 @@ pub extern "C" fn Servo_StyleSheet_FromUTF8Bytes(loader: *mut Loader,
                                                  data: *const nsACString,
                                                  mode: SheetParsingMode,
                                                  base_url: *const nsACString,
-                                                 base: *mut ThreadSafeURIHolder,
-                                                 referrer: *mut ThreadSafeURIHolder,
-                                                 principal: *mut ThreadSafePrincipalHolder)
+                                                 extra_data: *mut URLExtraData)
                                                  -> RawServoStyleSheetStrong {
     let global_style_data = &*GLOBAL_STYLE_DATA;
     let input = unsafe { data.as_ref().unwrap().as_str_unchecked() };
@@ -346,11 +343,7 @@ pub extern "C" fn Servo_StyleSheet_FromUTF8Bytes(loader: *mut Loader,
 
     let base_str = unsafe { base_url.as_ref().unwrap().as_str_unchecked() };
     let url = ServoUrl::parse(base_str).unwrap();
-    let extra_data = unsafe { ParserContextExtraData {
-        base: Some(GeckoArcURI::new(base)),
-        referrer: Some(GeckoArcURI::new(referrer)),
-        principal: Some(GeckoArcPrincipal::new(principal)),
-    }};
+    let extra_data = unsafe { ParserContextExtraData::new(extra_data) };
     let loader = if loader.is_null() {
         None
     } else {
@@ -375,16 +368,10 @@ pub extern "C" fn Servo_StyleSheet_ClearAndUpdate(stylesheet: RawServoStyleSheet
                                                   loader: *mut Loader,
                                                   gecko_stylesheet: *mut ServoStyleSheet,
                                                   data: *const nsACString,
-                                                  base: *mut ThreadSafeURIHolder,
-                                                  referrer: *mut ThreadSafeURIHolder,
-                                                  principal: *mut ThreadSafePrincipalHolder)
+                                                  extra_data: *mut URLExtraData)
 {
     let input = unsafe { data.as_ref().unwrap().as_str_unchecked() };
-    let extra_data = unsafe { ParserContextExtraData {
-        base: Some(GeckoArcURI::new(base)),
-        referrer: Some(GeckoArcURI::new(referrer)),
-        principal: Some(GeckoArcPrincipal::new(principal)),
-    }};
+    let extra_data = unsafe { ParserContextExtraData::new(extra_data) };
 
     let loader = if loader.is_null() {
         None
@@ -792,7 +779,7 @@ macro_rules! make_context {
 #[no_mangle]
 pub extern "C" fn Servo_ParseProperty(property: *const nsACString, value: *const nsACString,
                                       base: *const nsACString,
-                                      data: *const structs::GeckoParserExtraData)
+                                      data: *mut URLExtraData)
                                       -> RawServoDeclarationBlockStrong {
     let name = unsafe { property.as_ref().unwrap().as_str_unchecked() };
     let id = if let Ok(id) = PropertyId::parse(name.into()) {
@@ -824,7 +811,7 @@ pub extern "C" fn Servo_ParseProperty(property: *const nsACString, value: *const
 #[no_mangle]
 pub extern "C" fn Servo_ParseEasing(easing: *const nsAString,
                                     base: *const nsACString,
-                                    data: *const structs::GeckoParserExtraData,
+                                    data: *mut URLExtraData,
                                     output: nsTimingFunctionBorrowedMut)
                                     -> bool {
     use style::properties::longhands::transition_timing_function;
@@ -845,7 +832,7 @@ pub extern "C" fn Servo_ParseEasing(easing: *const nsAString,
 #[no_mangle]
 pub extern "C" fn Servo_ParseStyleAttribute(data: *const nsACString,
                                             base: *const nsACString,
-                                            raw_extra_data: *const structs::GeckoParserExtraData)
+                                            raw_extra_data: *mut URLExtraData)
                                             -> RawServoDeclarationBlockStrong {
     let global_style_data = &*GLOBAL_STYLE_DATA;
     let value = unsafe { data.as_ref().unwrap().as_str_unchecked() };
@@ -965,7 +952,7 @@ pub extern "C" fn Servo_DeclarationBlock_GetPropertyIsImportant(declarations: Ra
 
 fn set_property(declarations: RawServoDeclarationBlockBorrowed, property_id: PropertyId,
                 value: *const nsACString, is_important: bool,
-                base: *const nsACString, data: *const structs::GeckoParserExtraData) -> bool {
+                base: *const nsACString, data: *mut URLExtraData) -> bool {
     let value = unsafe { value.as_ref().unwrap().as_str_unchecked() };
 
     make_context!((base, data) => (base_url, extra_data));
@@ -985,7 +972,7 @@ pub extern "C" fn Servo_DeclarationBlock_SetProperty(declarations: RawServoDecla
                                                      property: *const nsACString, value: *const nsACString,
                                                      is_important: bool,
                                                      base: *const nsACString,
-                                                     data: *const structs::GeckoParserExtraData) -> bool {
+                                                     data: *mut URLExtraData) -> bool {
     set_property(declarations, get_property_id_from_property!(property, false),
                  value, is_important, base, data)
 }
@@ -995,7 +982,7 @@ pub extern "C" fn Servo_DeclarationBlock_SetPropertyById(declarations: RawServoD
                                                          property: nsCSSPropertyID, value: *const nsACString,
                                                          is_important: bool,
                                                          base: *const nsACString,
-                                                         data: *const structs::GeckoParserExtraData) -> bool {
+                                                         data: *mut URLExtraData) -> bool {
     set_property(declarations, get_property_id_from_nscsspropertyid!(property, false),
                  value, is_important, base, data)
 }
diff --git a/ports/geckolib/stylesheet_loader.rs b/ports/geckolib/stylesheet_loader.rs
index cc81a267b48..78a859cc64e 100644
--- a/ports/geckolib/stylesheet_loader.rs
+++ b/ports/geckolib/stylesheet_loader.rs
@@ -44,13 +44,13 @@ impl StyleStylesheetLoader for StylesheetLoader {
         // so this raw pointer will still be valid.
         let (spec_bytes, spec_len): (*const u8, usize) = import.url.as_slice_components();
 
-        let base_uri = import.url.base.mRawPtr;
+        let base_url_data = import.url.extra_data.get();
         let arc = make_arc(import);
         unsafe {
             Gecko_LoadStyleSheet(self.0,
                                  self.1,
                                  HasArcFFI::arc_as_borrowed(&arc),
-                                 base_uri,
+                                 base_url_data,
                                  spec_bytes,
                                  spec_len as u32,
                                  media_string.as_bytes().as_ptr(),