Bug 1340958 - Templatize ComposeStyle. r=birtles

Later in this patch series we will replace ServoAnimationRule with a hashmap.
At that point, we would like to pass the hashmap to ComposeStyle. In order
to achieve that, this patch templatizes the 'animation rule' parameter of
ComposeStyle in both Animation and KeyframeEffectReadOnly so that it can
represent a hashmap instead.

MozReview-Commit-ID: H5bMxjN3W8n

--HG--
extra : rebase_source : 58cd9ee1cda51970d35c52b39d2cdab12055e24a

dom/animation/Animation.cpp

@@ -14,6 +14,7 @@
 #include "mozilla/AsyncEventDispatcher.h" // For AsyncEventDispatcher
 #include "mozilla/Maybe.h" // For Maybe
 #include "mozilla/AnimationRule.h" // For AnimationRule
+#include "mozilla/TypeTraits.h" // For Forward<>
 #include "nsAnimationManager.h" // For CSSAnimation
 #include "nsDOMMutationObserver.h" // For nsAutoAnimationMutationBatch
 #include "nsIDocument.h" // For nsIDocument
@@ -942,8 +943,9 @@ Animation::WillComposeStyle()
   }
 }
 
+template<typename ComposeAnimationResult>
 void
-Animation::ComposeStyle(AnimationRule& aStyleRule,
+Animation::ComposeStyle(ComposeAnimationResult&& aComposeResult,
                         const nsCSSPropertyIDSet& aPropertiesToSkip)
 {
   if (!mEffect) {
@@ -1005,7 +1007,8 @@ Animation::ComposeStyle(AnimationRule& aStyleRule,
 
     KeyframeEffectReadOnly* keyframeEffect = mEffect->AsKeyframeEffect();
     if (keyframeEffect) {
-      keyframeEffect->ComposeStyle(aStyleRule, aPropertiesToSkip);
+      keyframeEffect->ComposeStyle(Forward<ComposeAnimationResult>(aComposeResult),
+                                   aPropertiesToSkip);
     }
   }
 
@@ -1506,5 +1509,17 @@ Animation::IsRunningOnCompositor() const
          mEffect->AsKeyframeEffect()->IsRunningOnCompositor();
 }
 
+template
+void
+Animation::ComposeStyle<RefPtr<AnimValuesStyleRule>&>(
+  RefPtr<AnimValuesStyleRule>& aAnimationRule,
+  const nsCSSPropertyIDSet& aPropertiesToSkip);
+
+template
+void
+Animation::ComposeStyle<RefPtr<ServoAnimationRule>&>(
+  RefPtr<ServoAnimationRule>& aAnimationRule,
+  const nsCSSPropertyIDSet& aPropertiesToSkip);
+
 } // namespace dom
 } // namespace mozilla

dom/animation/Animation.h

@@ -321,12 +321,13 @@ public:
   void WillComposeStyle();
 
   /**
-   * Updates |aStyleRule| with the animation values of this animation's effect,
-   * if any.
+   * Updates |aComposeResult| with the animation values of this animation's
+   * effect, if any.
    * Any properties contained in |aPropertiesToSkip| will not be added or
-   * updated in |aStyleRule|.
+   * updated in |aComposeResult|.
    */
-  void ComposeStyle(AnimationRule& aStyleRule,
+  template<typename ComposeAnimationResult>
+  void ComposeStyle(ComposeAnimationResult&& aComposeResult,
                     const nsCSSPropertyIDSet& aPropertiesToSkip);
 
   void NotifyEffectTimingUpdated();

dom/animation/EffectCompositor.cpp

@@ -508,7 +508,7 @@ EffectCompositor::GetServoAnimationRule(const dom::Element* aElement,
       ? effectSet->PropertiesForAnimationsLevel().Inverse()
       : effectSet->PropertiesForAnimationsLevel();
   for (KeyframeEffectReadOnly* effect : sortedEffectList) {
-    effect->GetAnimation()->ComposeStyle(animRule, propertiesToSkip);
+    effect->GetAnimation()->ComposeStyle(animRule.mServo, propertiesToSkip);
   }
 
   MOZ_ASSERT(effectSet == EffectSet::GetEffectSet(aElement, aPseudoType),
@@ -783,7 +783,7 @@ EffectCompositor::ComposeAnimationRule(dom::Element* aElement,
     : effects->PropertiesForAnimationsLevel();
   for (KeyframeEffectReadOnly* effect : sortedEffectList) {
     effect->GetAnimation()->WillComposeStyle();
-    effect->GetAnimation()->ComposeStyle(animRule, propertiesToSkip);
+    effect->GetAnimation()->ComposeStyle(animRule.mGecko, propertiesToSkip);
   }
 
   MOZ_ASSERT(effects == EffectSet::GetEffectSet(aElement, aPseudoType),

dom/animation/KeyframeEffectReadOnly.cpp

@@ -649,9 +649,10 @@ KeyframeEffectReadOnly::ComposeStyleRule(
   }
 }
 
+template<typename ComposeAnimationResult>
 void
 KeyframeEffectReadOnly::ComposeStyle(
-  AnimationRule& aStyleRule,
+  ComposeAnimationResult&& aComposeResult,
   const nsCSSPropertyIDSet& aPropertiesToSkip)
 {
   MOZ_DIAGNOSTIC_ASSERT(!mIsComposingStyle,
@@ -671,8 +672,6 @@ KeyframeEffectReadOnly::ComposeStyle(
     return;
   }
 
-  bool isServoBackend = mDocument->IsStyledByServo();
-
   for (size_t propIdx = 0, propEnd = mProperties.Length();
        propIdx != propEnd; ++propIdx)
   {
@@ -706,17 +705,10 @@ KeyframeEffectReadOnly::ComposeStyle(
                  prop.mSegments.Length(),
                "out of array bounds");
 
-    if (isServoBackend) {
-      ComposeStyleRule(aStyleRule.mServo,
-                       prop,
-                       *segment,
-                       computedTiming);
-    } else {
-      ComposeStyleRule(aStyleRule.mGecko,
-                       prop,
-                       *segment,
-                       computedTiming);
-    }
+    ComposeStyleRule(Forward<ComposeAnimationResult>(aComposeResult),
+                     prop,
+                     *segment,
+                     computedTiming);
   }
 }
 
@@ -1821,5 +1813,17 @@ KeyframeEffectReadOnly::ContainsAnimatedScale(const nsIFrame* aFrame) const
   return false;
 }
 
+template
+void
+KeyframeEffectReadOnly::ComposeStyle<RefPtr<AnimValuesStyleRule>&>(
+  RefPtr<AnimValuesStyleRule>& aAnimationRule,
+  const nsCSSPropertyIDSet& aPropertiesToSkip);
+
+template
+void
+KeyframeEffectReadOnly::ComposeStyle<RefPtr<ServoAnimationRule>&>(
+  RefPtr<ServoAnimationRule>& aAnimationRule,
+  const nsCSSPropertyIDSet& aPropertiesToSkip);
+
 } // namespace dom
 } // namespace mozilla

dom/animation/KeyframeEffectReadOnly.h

@@ -255,10 +255,11 @@ public:
   // parallel traversal.
   void WillComposeStyle();
 
-  // Updates |aStyleRule| with the animation values produced by this
+  // Updates |aComposeResult| with the animation values produced by this
   // AnimationEffect for the current time except any properties contained
   // in |aPropertiesToSkip|.
-  void ComposeStyle(AnimationRule& aStyleRule,
+  template<typename ComposeAnimationResult>
+  void ComposeStyle(ComposeAnimationResult&& aRestultContainer,
                     const nsCSSPropertyIDSet& aPropertiesToSkip);
 
   // Composite |aValueToComposite| on |aUnderlyingValue| with