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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---
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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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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;

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()
     }