Bug 1368889 - Post animation restyle hint againt pseudo element instead of its parent. r=birtles

To traverse pseudo elements in animation-only restyle, the pseudo element
itself needs the animation-only dirty bit.

MozReview-Commit-ID: 11RfVqnPXfJ

--HG--
extra : rebase_source : d048c9a053c03bf3fef46fcbfd9cbd5f60204e1d

dom/animation/EffectCompositor.cpp

@@ -1042,6 +1042,7 @@ EffectCompositor::PreTraverseInSubtree(Element* aRoot,
       // middle of the servo traversal.
       mPresContext->RestyleManager()->AsServo()->
         PostRestyleEventForAnimations(target.mElement,
+                                      target.mPseudoType,
                                       cascadeLevel == CascadeLevel::Transitions
                                         ? eRestyle_CSSTransitions
                                         : eRestyle_CSSAnimations);
@@ -1108,6 +1109,7 @@ EffectCompositor::PreTraverse(dom::Element* aElement,
 
     mPresContext->RestyleManager()->AsServo()->
       PostRestyleEventForAnimations(aElement,
+                                    aPseudoType,
                                     cascadeLevel == CascadeLevel::Transitions
                                       ? eRestyle_CSSTransitions
                                       : eRestyle_CSSAnimations);

dom/animation/EffectCompositor.h

@@ -249,6 +249,15 @@ public:
   bool PreTraverseInSubtree(dom::Element* aElement,
                             AnimationRestyleType aRestyleType);
 
+  // Returns the target element for restyling.
+  //
+  // If |aPseudoType| is ::after or ::before, returns the generated content
+  // element of which |aElement| is the parent. If |aPseudoType| is any other
+  // pseudo type (other thant CSSPseudoElementType::NotPseudo) returns nullptr.
+  // Otherwise, returns |aElement|.
+  static dom::Element* GetElementToRestyle(dom::Element* aElement,
+                                           CSSPseudoElementType aPseudoType);
+
 private:
   ~EffectCompositor() = default;
 
@@ -258,10 +267,6 @@ private:
                                    CSSPseudoElementType aPseudoType,
                                    CascadeLevel aCascadeLevel);
 
-  static dom::Element* GetElementToRestyle(dom::Element* aElement,
-                                           CSSPseudoElementType
-                                             aPseudoType);
-
   // Get the properties in |aEffectSet| that we are able to animate on the
   // compositor but which are also specified at a higher level in the cascade
   // than the animations level.

dom/smil/nsSMILAnimationController.cpp

@@ -767,6 +767,7 @@ nsSMILAnimationController::PreTraverseInSubtree(Element* aRoot)
 
     context->RestyleManager()->AsServo()->
       PostRestyleEventForAnimations(key.mElement,
+                                    CSSPseudoElementType::NotPseudo,
                                     eRestyle_StyleAttribute_Animations);
 
     foundElementsNeedingRestyle = true;

layout/base/ServoRestyleManager.cpp

@@ -74,10 +74,22 @@ ServoRestyleManager::PostRestyleEventForCSSRuleChanges()
 }
 
 /* static */ void
-ServoRestyleManager::PostRestyleEventForAnimations(Element* aElement,
-                                                   nsRestyleHint aRestyleHint)
+ServoRestyleManager::PostRestyleEventForAnimations(
+  Element* aElement,
+  CSSPseudoElementType aPseudoType,
+  nsRestyleHint aRestyleHint)
 {
-  Servo_NoteExplicitHints(aElement, aRestyleHint, nsChangeHint(0));
+  Element* elementToRestyle =
+    EffectCompositor::GetElementToRestyle(aElement, aPseudoType);
+
+  if (!elementToRestyle) {
+    // FIXME: Bug 1371107: When reframing happens,
+    // EffectCompositor::mElementsToRestyle still has unbinded old pseudo
+    // element. We should drop it.
+    return;
+  }
+
+  Servo_NoteExplicitHints(elementToRestyle, aRestyleHint, nsChangeHint(0));
 }
 
 void

layout/base/ServoRestyleManager.h

@@ -107,6 +107,7 @@ public:
    * traversal of the same restyling process.
    */
   static void PostRestyleEventForAnimations(dom::Element* aElement,
+                                            CSSPseudoElementType aPseudoType,
                                             nsRestyleHint aRestyleHint);
 protected:
   ~ServoRestyleManager() override

layout/style/test/stylo-failures.md

@@ -42,7 +42,6 @@ to mochitest command.
   * test_bug413958.html `monitorConsole` [3]
   * test_parser_diagnostics_unprintables.html [550]
 * Transition support:
-  * test_transitions.html: pseudo elements [4]
   * test_transitions_and_reframes.html `pseudo-element`: bug 1366422 [4]
   * Events:
     * test_animations_event_order.html [2]