Auto merge of #18577 - moz-servo-sync:gecko-backout, r=moz-servo-sync

Backed out changeset 5b56ebe80e22 (bug 1400438) for heap write hazard. r=backout

Backed out changeset 5b56ebe80e22 (bug 1400438) for heap write hazard. r=backout

Backs out https://github.com/servo/servo/pull/18574

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4 files changed, 102 insertions, 176 deletions

diff --git a/components/style/gecko/generated/bindings.rs b/components/style/gecko/generated/bindings.rs
index 5a5a624b160..59c97a0658e 100644
--- a/components/style/gecko/generated/bindings.rs
+++ b/components/style/gecko/generated/bindings.rs
@@ -71,6 +71,7 @@ use gecko_bindings::structs::StyleBasicShapeType;
 use gecko_bindings::structs::StyleShapeSource;
 use gecko_bindings::structs::StyleTransition;
 use gecko_bindings::structs::gfxFontFeatureValueSet;
+use gecko_bindings::structs::nsBorderColors;
 use gecko_bindings::structs::nsCSSCounterStyleRule;
 use gecko_bindings::structs::nsCSSFontFaceRule;
 use gecko_bindings::structs::nsCSSKeyword;
@@ -876,10 +877,22 @@ extern "C" {
     pub fn Gecko_EnsureMozBorderColors(aBorder: *mut nsStyleBorder);
 }
 extern "C" {
+    pub fn Gecko_ClearMozBorderColors(aBorder: *mut nsStyleBorder,
+                                      aSide: Side);
+}
+extern "C" {
+    pub fn Gecko_AppendMozBorderColors(aBorder: *mut nsStyleBorder,
+                                       aSide: Side, aColor: nscolor);
+}
+extern "C" {
     pub fn Gecko_CopyMozBorderColors(aDest: *mut nsStyleBorder,
                                      aSrc: *const nsStyleBorder, aSide: Side);
 }
 extern "C" {
+    pub fn Gecko_GetMozBorderColors(aBorder: *const nsStyleBorder,
+                                    aSide: Side) -> *const nsBorderColors;
+}
+extern "C" {
     pub fn Gecko_FontFamilyList_Clear(aList: *mut FontFamilyList);
 }
 extern "C" {
diff --git a/components/style/gecko/generated/structs_debug.rs b/components/style/gecko/generated/structs_debug.rs
index 5f4e696f5ea..59807d919eb 100644
--- a/components/style/gecko/generated/structs_debug.rs
+++ b/components/style/gecko/generated/structs_debug.rs
@@ -14284,7 +14284,7 @@ pub mod root {
     #[repr(C)]
     #[derive(Debug)]
     pub struct nsStyleBorder {
-        pub mBorderColors: root::mozilla::UniquePtr<root::nsBorderColors>,
+        pub mBorderColors: *mut *mut root::nsBorderColors,
         pub mBorderRadius: root::nsStyleCorners,
         pub mBorderImageSource: root::nsStyleImage,
         pub mBorderImageSlice: root::nsStyleSides,
@@ -30544,6 +30544,29 @@ pub mod root {
     }
     #[repr(C)]
     #[derive(Debug)]
+    pub struct nsBorderColors {
+        pub mNext: *mut root::nsBorderColors,
+        pub mColor: root::nscolor,
+    }
+    #[test]
+    fn bindgen_test_layout_nsBorderColors() {
+        assert_eq!(::std::mem::size_of::<nsBorderColors>() , 16usize , concat
+                   ! ( "Size of: " , stringify ! ( nsBorderColors ) ));
+        assert_eq! (::std::mem::align_of::<nsBorderColors>() , 8usize , concat
+                    ! ( "Alignment of " , stringify ! ( nsBorderColors ) ));
+        assert_eq! (unsafe {
+                    & ( * ( 0 as * const nsBorderColors ) ) . mNext as * const
+                    _ as usize } , 0usize , concat ! (
+                    "Alignment of field: " , stringify ! ( nsBorderColors ) ,
+                    "::" , stringify ! ( mNext ) ));
+        assert_eq! (unsafe {
+                    & ( * ( 0 as * const nsBorderColors ) ) . mColor as *
+                    const _ as usize } , 8usize , concat ! (
+                    "Alignment of field: " , stringify ! ( nsBorderColors ) ,
+                    "::" , stringify ! ( mColor ) ));
+    }
+    #[repr(C)]
+    #[derive(Debug)]
     pub struct nsCSSShadowItem {
         pub mXOffset: root::nscoord,
         pub mYOffset: root::nscoord,
@@ -30628,23 +30651,6 @@ pub mod root {
                     "Alignment of field: " , stringify ! ( nsCSSShadowArray )
                     , "::" , stringify ! ( mArray ) ));
     }
-    #[repr(C)]
-    #[derive(Debug)]
-    pub struct nsBorderColors {
-        pub mColors: [root::nsTArray<::std::os::raw::c_uint>; 4usize],
-    }
-    #[test]
-    fn bindgen_test_layout_nsBorderColors() {
-        assert_eq!(::std::mem::size_of::<nsBorderColors>() , 32usize , concat
-                   ! ( "Size of: " , stringify ! ( nsBorderColors ) ));
-        assert_eq! (::std::mem::align_of::<nsBorderColors>() , 8usize , concat
-                    ! ( "Alignment of " , stringify ! ( nsBorderColors ) ));
-        assert_eq! (unsafe {
-                    & ( * ( 0 as * const nsBorderColors ) ) . mColors as *
-                    const _ as usize } , 0usize , concat ! (
-                    "Alignment of field: " , stringify ! ( nsBorderColors ) ,
-                    "::" , stringify ! ( mColors ) ));
-    }
     /// An object that allows sharing of arrays that store 'quotes' property
     /// values.  This is particularly important for inheritance, where we want
     /// to share the same 'quotes' value with a parent style context.
@@ -33513,28 +33519,6 @@ pub mod root {
                    root::RefPtr<root::nsCSSValueSharedList> ) ));
     }
     #[test]
-    fn __bindgen_test_layout_UniquePtr_open0_nsBorderColors_DefaultDelete_open1_nsBorderColors_close1_close0_instantiation() {
-        assert_eq!(::std::mem::size_of::<root::mozilla::UniquePtr<root::nsBorderColors>>()
-                   , 8usize , concat ! (
-                   "Size of template specialization: " , stringify ! (
-                   root::mozilla::UniquePtr<root::nsBorderColors> ) ));
-        assert_eq!(::std::mem::align_of::<root::mozilla::UniquePtr<root::nsBorderColors>>()
-                   , 8usize , concat ! (
-                   "Alignment of template specialization: " , stringify ! (
-                   root::mozilla::UniquePtr<root::nsBorderColors> ) ));
-    }
-    #[test]
-    fn __bindgen_test_layout_DefaultDelete_open0_nsBorderColors_close0_instantiation() {
-        assert_eq!(::std::mem::size_of::<root::mozilla::DefaultDelete>() ,
-                   1usize , concat ! (
-                   "Size of template specialization: " , stringify ! (
-                   root::mozilla::DefaultDelete ) ));
-        assert_eq!(::std::mem::align_of::<root::mozilla::DefaultDelete>() ,
-                   1usize , concat ! (
-                   "Alignment of template specialization: " , stringify ! (
-                   root::mozilla::DefaultDelete ) ));
-    }
-    #[test]
     fn __bindgen_test_layout_nsTArray_open0_nsStyleFilter_close0_instantiation() {
         assert_eq!(::std::mem::size_of::<root::nsTArray<root::nsStyleFilter>>()
                    , 8usize , concat ! (
@@ -33590,17 +33574,6 @@ pub mod root {
                    root::nsTArray<::nsstring::nsStringRepr> ) ));
     }
     #[test]
-    fn __bindgen_test_layout_nsTString_open0_char16_t_close0_instantiation_2() {
-        assert_eq!(::std::mem::size_of::<::nsstring::nsStringRepr>() , 16usize ,
-                   concat ! (
-                   "Size of template specialization: " , stringify ! (
-                   ::nsstring::nsStringRepr ) ));
-        assert_eq!(::std::mem::align_of::<::nsstring::nsStringRepr>() , 8usize ,
-                   concat ! (
-                   "Alignment of template specialization: " , stringify ! (
-                   ::nsstring::nsStringRepr ) ));
-    }
-    #[test]
     fn __bindgen_test_layout_nsTArray_open0__bindgen_ty_id_202536_close0_instantiation() {
         assert_eq!(::std::mem::size_of::<root::nsTArray<*mut root::mozilla::StyleSheet>>()
                    , 8usize , concat ! (
@@ -34833,17 +34806,6 @@ pub mod root {
                    root::nsTArray<::nsstring::nsStringRepr> ) ));
     }
     #[test]
-    fn __bindgen_test_layout_nsTString_open0_char16_t_close0_instantiation_3() {
-        assert_eq!(::std::mem::size_of::<::nsstring::nsStringRepr>() , 16usize ,
-                   concat ! (
-                   "Size of template specialization: " , stringify ! (
-                   ::nsstring::nsStringRepr ) ));
-        assert_eq!(::std::mem::align_of::<::nsstring::nsStringRepr>() , 8usize ,
-                   concat ! (
-                   "Alignment of template specialization: " , stringify ! (
-                   ::nsstring::nsStringRepr ) ));
-    }
-    #[test]
     fn __bindgen_test_layout_nsTArray_open0__bindgen_ty_id_213307_close0_instantiation() {
         assert_eq!(::std::mem::size_of::<root::nsTArray<*mut root::mozilla::StyleSheet>>()
                    , 8usize , concat ! (
@@ -36742,17 +36704,6 @@ pub mod root {
                    ));
     }
     #[test]
-    fn __bindgen_test_layout_nsTArray_open0_unsigned_int_close0_instantiation_5() {
-        assert_eq!(::std::mem::size_of::<root::nsTArray<::std::os::raw::c_uint>>()
-                   , 8usize , concat ! (
-                   "Size of template specialization: " , stringify ! (
-                   root::nsTArray<::std::os::raw::c_uint> ) ));
-        assert_eq!(::std::mem::align_of::<root::nsTArray<::std::os::raw::c_uint>>()
-                   , 8usize , concat ! (
-                   "Alignment of template specialization: " , stringify ! (
-                   root::nsTArray<::std::os::raw::c_uint> ) ));
-    }
-    #[test]
     fn __bindgen_test_layout_nsTArray_open0_pair_open1_nsString_nsString_close1_close0_instantiation() {
         assert_eq!(::std::mem::size_of::<root::nsTArray<root::std::pair<::nsstring::nsStringRepr,
                                                      ::nsstring::nsStringRepr>>>()
diff --git a/components/style/gecko/generated/structs_release.rs b/components/style/gecko/generated/structs_release.rs
index faf3924a299..dd1e0f487bd 100644
--- a/components/style/gecko/generated/structs_release.rs
+++ b/components/style/gecko/generated/structs_release.rs
@@ -14131,7 +14131,7 @@ pub mod root {
     #[repr(C)]
     #[derive(Debug)]
     pub struct nsStyleBorder {
-        pub mBorderColors: root::mozilla::UniquePtr<root::nsBorderColors>,
+        pub mBorderColors: *mut *mut root::nsBorderColors,
         pub mBorderRadius: root::nsStyleCorners,
         pub mBorderImageSource: root::nsStyleImage,
         pub mBorderImageSlice: root::nsStyleSides,
@@ -30130,6 +30130,29 @@ pub mod root {
     }
     #[repr(C)]
     #[derive(Debug)]
+    pub struct nsBorderColors {
+        pub mNext: *mut root::nsBorderColors,
+        pub mColor: root::nscolor,
+    }
+    #[test]
+    fn bindgen_test_layout_nsBorderColors() {
+        assert_eq!(::std::mem::size_of::<nsBorderColors>() , 16usize , concat
+                   ! ( "Size of: " , stringify ! ( nsBorderColors ) ));
+        assert_eq! (::std::mem::align_of::<nsBorderColors>() , 8usize , concat
+                    ! ( "Alignment of " , stringify ! ( nsBorderColors ) ));
+        assert_eq! (unsafe {
+                    & ( * ( 0 as * const nsBorderColors ) ) . mNext as * const
+                    _ as usize } , 0usize , concat ! (
+                    "Alignment of field: " , stringify ! ( nsBorderColors ) ,
+                    "::" , stringify ! ( mNext ) ));
+        assert_eq! (unsafe {
+                    & ( * ( 0 as * const nsBorderColors ) ) . mColor as *
+                    const _ as usize } , 8usize , concat ! (
+                    "Alignment of field: " , stringify ! ( nsBorderColors ) ,
+                    "::" , stringify ! ( mColor ) ));
+    }
+    #[repr(C)]
+    #[derive(Debug)]
     pub struct nsCSSShadowItem {
         pub mXOffset: root::nscoord,
         pub mYOffset: root::nscoord,
@@ -30214,23 +30237,6 @@ pub mod root {
                     "Alignment of field: " , stringify ! ( nsCSSShadowArray )
                     , "::" , stringify ! ( mArray ) ));
     }
-    #[repr(C)]
-    #[derive(Debug)]
-    pub struct nsBorderColors {
-        pub mColors: [root::nsTArray<::std::os::raw::c_uint>; 4usize],
-    }
-    #[test]
-    fn bindgen_test_layout_nsBorderColors() {
-        assert_eq!(::std::mem::size_of::<nsBorderColors>() , 32usize , concat
-                   ! ( "Size of: " , stringify ! ( nsBorderColors ) ));
-        assert_eq! (::std::mem::align_of::<nsBorderColors>() , 8usize , concat
-                    ! ( "Alignment of " , stringify ! ( nsBorderColors ) ));
-        assert_eq! (unsafe {
-                    & ( * ( 0 as * const nsBorderColors ) ) . mColors as *
-                    const _ as usize } , 0usize , concat ! (
-                    "Alignment of field: " , stringify ! ( nsBorderColors ) ,
-                    "::" , stringify ! ( mColors ) ));
-    }
     /// An object that allows sharing of arrays that store 'quotes' property
     /// values.  This is particularly important for inheritance, where we want
     /// to share the same 'quotes' value with a parent style context.
@@ -33099,28 +33105,6 @@ pub mod root {
                    root::RefPtr<root::nsCSSValueSharedList> ) ));
     }
     #[test]
-    fn __bindgen_test_layout_UniquePtr_open0_nsBorderColors_DefaultDelete_open1_nsBorderColors_close1_close0_instantiation() {
-        assert_eq!(::std::mem::size_of::<root::mozilla::UniquePtr<root::nsBorderColors>>()
-                   , 8usize , concat ! (
-                   "Size of template specialization: " , stringify ! (
-                   root::mozilla::UniquePtr<root::nsBorderColors> ) ));
-        assert_eq!(::std::mem::align_of::<root::mozilla::UniquePtr<root::nsBorderColors>>()
-                   , 8usize , concat ! (
-                   "Alignment of template specialization: " , stringify ! (
-                   root::mozilla::UniquePtr<root::nsBorderColors> ) ));
-    }
-    #[test]
-    fn __bindgen_test_layout_DefaultDelete_open0_nsBorderColors_close0_instantiation() {
-        assert_eq!(::std::mem::size_of::<root::mozilla::DefaultDelete>() ,
-                   1usize , concat ! (
-                   "Size of template specialization: " , stringify ! (
-                   root::mozilla::DefaultDelete ) ));
-        assert_eq!(::std::mem::align_of::<root::mozilla::DefaultDelete>() ,
-                   1usize , concat ! (
-                   "Alignment of template specialization: " , stringify ! (
-                   root::mozilla::DefaultDelete ) ));
-    }
-    #[test]
     fn __bindgen_test_layout_nsTArray_open0_nsStyleFilter_close0_instantiation() {
         assert_eq!(::std::mem::size_of::<root::nsTArray<root::nsStyleFilter>>()
                    , 8usize , concat ! (
@@ -33176,17 +33160,6 @@ pub mod root {
                    root::nsTArray<::nsstring::nsStringRepr> ) ));
     }
     #[test]
-    fn __bindgen_test_layout_nsTString_open0_char16_t_close0_instantiation_2() {
-        assert_eq!(::std::mem::size_of::<::nsstring::nsStringRepr>() , 16usize ,
-                   concat ! (
-                   "Size of template specialization: " , stringify ! (
-                   ::nsstring::nsStringRepr ) ));
-        assert_eq!(::std::mem::align_of::<::nsstring::nsStringRepr>() , 8usize ,
-                   concat ! (
-                   "Alignment of template specialization: " , stringify ! (
-                   ::nsstring::nsStringRepr ) ));
-    }
-    #[test]
     fn __bindgen_test_layout_nsTArray_open0__bindgen_ty_id_200130_close0_instantiation() {
         assert_eq!(::std::mem::size_of::<root::nsTArray<*mut root::mozilla::StyleSheet>>()
                    , 8usize , concat ! (
@@ -34419,17 +34392,6 @@ pub mod root {
                    root::nsTArray<::nsstring::nsStringRepr> ) ));
     }
     #[test]
-    fn __bindgen_test_layout_nsTString_open0_char16_t_close0_instantiation_3() {
-        assert_eq!(::std::mem::size_of::<::nsstring::nsStringRepr>() , 16usize ,
-                   concat ! (
-                   "Size of template specialization: " , stringify ! (
-                   ::nsstring::nsStringRepr ) ));
-        assert_eq!(::std::mem::align_of::<::nsstring::nsStringRepr>() , 8usize ,
-                   concat ! (
-                   "Alignment of template specialization: " , stringify ! (
-                   ::nsstring::nsStringRepr ) ));
-    }
-    #[test]
     fn __bindgen_test_layout_nsTArray_open0__bindgen_ty_id_210857_close0_instantiation() {
         assert_eq!(::std::mem::size_of::<root::nsTArray<*mut root::mozilla::StyleSheet>>()
                    , 8usize , concat ! (
@@ -36315,17 +36277,6 @@ pub mod root {
                    ));
     }
     #[test]
-    fn __bindgen_test_layout_nsTArray_open0_unsigned_int_close0_instantiation_5() {
-        assert_eq!(::std::mem::size_of::<root::nsTArray<::std::os::raw::c_uint>>()
-                   , 8usize , concat ! (
-                   "Size of template specialization: " , stringify ! (
-                   root::nsTArray<::std::os::raw::c_uint> ) ));
-        assert_eq!(::std::mem::align_of::<root::nsTArray<::std::os::raw::c_uint>>()
-                   , 8usize , concat ! (
-                   "Alignment of template specialization: " , stringify ! (
-                   root::nsTArray<::std::os::raw::c_uint> ) ));
-    }
-    #[test]
     fn __bindgen_test_layout_nsTArray_open0_pair_open1_nsString_nsString_close1_close0_instantiation() {
         assert_eq!(::std::mem::size_of::<root::nsTArray<root::std::pair<::nsstring::nsStringRepr,
                                                      ::nsstring::nsStringRepr>>>()
diff --git a/components/style/properties/gecko.mako.rs b/components/style/properties/gecko.mako.rs
index 19add7085f4..1d8ff1bf08d 100644
--- a/components/style/properties/gecko.mako.rs
+++ b/components/style/properties/gecko.mako.rs
@@ -1272,34 +1272,6 @@ fn static_assert() {
                                   border-image-repeat border-image-width border-image-slice
                                   ${skip_moz_border_color_longhands}">
 
-    fn set_moz_border_colors(&mut self, side: structs::Side, v: Option<Vec<::cssparser::RGBA>>) {
-        match v {
-            None => {
-                let ptr = self.gecko.mBorderColors.mPtr;
-                if let Some(colors) = unsafe { ptr.as_mut() } {
-                    unsafe { colors.mColors[side as usize].clear() };
-                }
-            }
-            Some(ref colors) => {
-                unsafe { bindings::Gecko_EnsureMozBorderColors(&mut self.gecko) };
-                let border_colors = unsafe { self.gecko.mBorderColors.mPtr.as_mut().unwrap() };
-                let dest_colors = &mut border_colors.mColors[side as usize];
-                unsafe { dest_colors.set_len_pod(colors.len() as u32) };
-                for (dst, src) in dest_colors.iter_mut().zip(colors.into_iter()) {
-                    *dst = convert_rgba_to_nscolor(src);
-                }
-            }
-        }
-    }
-
-    fn clone_moz_border_colors(&self, side: structs::Side) -> Option<Vec<::cssparser::RGBA>> {
-        unsafe { self.gecko.mBorderColors.mPtr.as_ref() }.map(|colors| {
-            colors.mColors[side as usize].iter()
-                .map(|color| convert_nscolor_to_rgba(*color))
-                .collect()
-        })
-    }
-
     % for side in SIDES:
     <% impl_keyword("border_%s_style" % side.ident,
                     "mBorderStyle[%s]" % side.index,
@@ -1350,7 +1322,29 @@ fn static_assert() {
     #[allow(non_snake_case)]
     pub fn set__moz_border_${side.ident}_colors(&mut self,
                                                 v: longhands::_moz_border_${side.ident}_colors::computed_value::T) {
-        self.set_moz_border_colors(structs::Side::eSide${to_camel_case(side.ident)}, v.0);
+        match v.0 {
+            None => {
+                unsafe {
+                    bindings::Gecko_ClearMozBorderColors(&mut self.gecko,
+                                                         structs::Side::eSide${to_camel_case(side.ident)});
+                }
+            },
+            Some(ref colors) => {
+                unsafe {
+                    bindings::Gecko_EnsureMozBorderColors(&mut self.gecko);
+                    bindings::Gecko_ClearMozBorderColors(&mut self.gecko,
+                                                         structs::Side::eSide${to_camel_case(side.ident)});
+                }
+                for color in colors {
+                    let c = convert_rgba_to_nscolor(color);
+                    unsafe {
+                        bindings::Gecko_AppendMozBorderColors(&mut self.gecko,
+                                                              structs::Side::eSide${to_camel_case(side.ident)},
+                                                              c);
+                    }
+                }
+            }
+        }
     }
 
     #[allow(non_snake_case)]
@@ -1370,7 +1364,24 @@ fn static_assert() {
     pub fn clone__moz_border_${side.ident}_colors(&self)
                                                   -> longhands::_moz_border_${side.ident}_colors::computed_value::T {
         use self::longhands::_moz_border_${side.ident}_colors::computed_value::T;
-        T(self.clone_moz_border_colors(structs::Side::eSide${to_camel_case(side.ident)}))
+
+        let mut gecko_colors =
+            unsafe { bindings::Gecko_GetMozBorderColors(&self.gecko,
+                                                        structs::Side::eSide${to_camel_case(side.ident)}) };
+
+        if gecko_colors.is_null() {
+            return T(None);
+        }
+
+        let mut colors = Vec::new();
+        loop {
+            unsafe {
+                colors.push(convert_nscolor_to_rgba((*gecko_colors).mColor));
+                if (*gecko_colors).mNext.is_null() { break; }
+                gecko_colors = (*gecko_colors).mNext;
+            }
+        }
+        T(Some(colors))
     }
     % endfor