Auto merge of #15910 - bzbarsky:anon-box-nofixup, r=emilio

Add support for skipping display fixup for pseudos.

This is needed for https://bugzilla.mozilla.org/show_bug.cgi?id=1346481

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- [X] `./mach build -d` does not report any errors
- [X] `./mach test-tidy` does not report any errors
- [ ] These changes fix #__ (github issue number if applicable).

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- [ ] There are tests for these changes OR
- [X] These changes do not require tests because will be tested on the Gecko side

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4 files changed, 24 insertions, 15 deletions

diff --git a/components/script_layout_interface/wrapper_traits.rs b/components/script_layout_interface/wrapper_traits.rs
index 5930538eac2..d8768384245 100644
--- a/components/script_layout_interface/wrapper_traits.rs
+++ b/components/script_layout_interface/wrapper_traits.rs
@@ -21,7 +21,7 @@ use style::context::SharedStyleContext;
 use style::data::ElementData;
 use style::dom::{LayoutIterator, NodeInfo, PresentationalHintsSynthetizer, TNode};
 use style::dom::OpaqueNode;
-use style::properties::ServoComputedValues;
+use style::properties::{CascadeFlags, ServoComputedValues};
 use style::selector_parser::{PseudoElement, PseudoElementCascadeType, SelectorImpl};
 
 #[derive(Copy, PartialEq, Clone, Debug)]
@@ -408,7 +408,7 @@ pub trait ThreadSafeLayoutElement: Clone + Copy + Sized + Debug +
                                     &style_pseudo,
                                     Some(data.styles().primary.values()),
                                     &context.default_computed_values,
-                                    false);
+                                    CascadeFlags::empty());
                             data.styles_mut().pseudos
                                 .insert(style_pseudo.clone(), new_style);
                         }
diff --git a/components/style/gecko_bindings/bindings.rs b/components/style/gecko_bindings/bindings.rs
index 2a92156fee4..e3faed75b5a 100644
--- a/components/style/gecko_bindings/bindings.rs
+++ b/components/style/gecko_bindings/bindings.rs
@@ -1666,6 +1666,7 @@ extern "C" {
     pub fn Servo_ComputedValues_GetForAnonymousBox(parent_style_or_null:
                                                        ServoComputedValuesBorrowedOrNull,
                                                    pseudoTag: *mut nsIAtom,
+                                                   skip_display_fixup: bool,
                                                    set:
                                                        RawServoStyleSetBorrowed)
      -> ServoComputedValuesStrong;
diff --git a/components/style/stylist.rs b/components/style/stylist.rs
index 5f7aef1666f..d75963b011b 100644
--- a/components/style/stylist.rs
+++ b/components/style/stylist.rs
@@ -14,7 +14,9 @@ use keyframes::KeyframesAnimation;
 use media_queries::Device;
 use parking_lot::RwLock;
 use pdqsort::sort_by;
-use properties::{self, CascadeFlags, ComputedValues, INHERIT_ALL};
+use properties::{self, CascadeFlags, ComputedValues};
+#[cfg(feature = "servo")]
+use properties::INHERIT_ALL;
 use properties::PropertyDeclarationBlock;
 use restyle_hints::{RestyleHint, DependencySet};
 use rule_tree::{CascadeLevel, RuleTree, StrongRuleNode, StyleSource};
@@ -294,7 +296,7 @@ impl Stylist {
                                          pseudo: &PseudoElement,
                                          parent: Option<&Arc<ComputedValues>>,
                                          default: &Arc<ComputedValues>,
-                                         inherit_all: bool)
+                                         cascade_flags: CascadeFlags)
                                          -> ComputedStyle {
         debug_assert!(SelectorImpl::pseudo_element_cascade_type(pseudo).is_precomputed());
 
@@ -308,11 +310,6 @@ impl Stylist {
             None => self.rule_tree.root(),
         };
 
-        let mut flags = CascadeFlags::empty();
-        if inherit_all {
-            flags.insert(INHERIT_ALL)
-        }
-
         // NOTE(emilio): We skip calculating the proper layout parent style
         // here.
         //
@@ -335,7 +332,7 @@ impl Stylist {
                                 default,
                                 None,
                                 Box::new(StdoutErrorReporter),
-                                flags);
+                                cascade_flags);
         ComputedStyle::new(rule_node, Arc::new(computed))
     }
 
@@ -363,7 +360,11 @@ impl Stylist {
                 unreachable!("That pseudo doesn't represent an anonymous box!")
             }
         };
-        self.precomputed_values_for_pseudo(&pseudo, Some(parent_style), default_style, inherit_all)
+        let mut cascade_flags = CascadeFlags::empty();
+        if inherit_all {
+            cascade_flags.insert(INHERIT_ALL);
+        }
+        self.precomputed_values_for_pseudo(&pseudo, Some(parent_style), default_style, cascade_flags)
             .values.unwrap()
     }
 
diff --git a/ports/geckolib/glue.rs b/ports/geckolib/glue.rs
index 2d8fc443792..eb51eb7ea09 100644
--- a/ports/geckolib/glue.rs
+++ b/ports/geckolib/glue.rs
@@ -67,8 +67,9 @@ use style::keyframes::KeyframesStepValue;
 use style::media_queries::{MediaList, parse_media_query_list};
 use style::parallel;
 use style::parser::{ParserContext, ParserContextExtraData};
-use style::properties::{ComputedValues, Importance, ParsedDeclaration};
+use style::properties::{CascadeFlags, ComputedValues, Importance, ParsedDeclaration};
 use style::properties::{PropertyDeclarationBlock, PropertyId};
+use style::properties::SKIP_ROOT_AND_ITEM_BASED_DISPLAY_FIXUP;
 use style::properties::animated_properties::{AnimationValue, Interpolate, TransitionProperty};
 use style::properties::parse_one_declaration;
 use style::restyle_hints::{self, RestyleHint};
@@ -618,8 +619,9 @@ pub extern "C" fn Servo_MediaRule_GetCssText(rule: RawServoMediaRuleBorrowed, re
 
 #[no_mangle]
 pub extern "C" fn Servo_ComputedValues_GetForAnonymousBox(parent_style_or_null: ServoComputedValuesBorrowedOrNull,
-                                                         pseudo_tag: *mut nsIAtom,
-                                                         raw_data: RawServoStyleSetBorrowed)
+                                                          pseudo_tag: *mut nsIAtom,
+                                                          skip_display_fixup: bool,
+                                                          raw_data: RawServoStyleSetBorrowed)
      -> ServoComputedValuesStrong {
     let data = PerDocumentStyleData::from_ffi(raw_data).borrow_mut();
     let atom = Atom::from(pseudo_tag);
@@ -627,8 +629,13 @@ pub extern "C" fn Servo_ComputedValues_GetForAnonymousBox(parent_style_or_null:
 
 
     let maybe_parent = ComputedValues::arc_from_borrowed(&parent_style_or_null);
+    let mut cascade_flags = CascadeFlags::empty();
+    if skip_display_fixup {
+        cascade_flags.insert(SKIP_ROOT_AND_ITEM_BASED_DISPLAY_FIXUP);
+    }
     data.stylist.precomputed_values_for_pseudo(&pseudo, maybe_parent,
-                                               data.default_computed_values(), false)
+                                               data.default_computed_values(),
+                                               cascade_flags)
         .values.unwrap()
         .into_strong()
 }