blink: Add backdrop-filter support

Source/core/animation/CompositorAnimations.cpp

Index: Source/core/animation/CompositorAnimations.cpp
diff --git a/Source/core/animation/CompositorAnimations.cpp b/Source/core/animation/CompositorAnimations.cpp
index 0c4154e14425832dd124b969c5bfa6742194d828..b675ed830aaf1e9e8313a1cc628e212054acfe3b 100644
--- a/Source/core/animation/CompositorAnimations.cpp
+++ b/Source/core/animation/CompositorAnimations.cpp
@@ -116,6 +116,7 @@ bool hasIncompatibleAnimations(const Element& targetElement, const Animation& an
     const bool affectsOpacity = effectToAdd.affects(PropertyHandle(CSSPropertyOpacity));
     const bool affectsTransform = effectToAdd.isTransformRelatedEffect();
     const bool affectsFilter = effectToAdd.affects(PropertyHandle(CSSPropertyWebkitFilter));
+    const bool affectsBackdropFilter = effectToAdd.affects(PropertyHandle(CSSPropertyBackdropFilter));
 
     if (!targetElement.hasAnimations())
         return false;
@@ -130,7 +131,8 @@ bool hasIncompatibleAnimations(const Element& targetElement, const Animation& an
 
         if ((affectsOpacity && attachedAnimation->affects(targetElement, CSSPropertyOpacity))
             || (affectsTransform && isTransformRelatedAnimation(targetElement, attachedAnimation))
-            || (affectsFilter && attachedAnimation->affects(targetElement, CSSPropertyWebkitFilter)))
+            || (affectsFilter && attachedAnimation->affects(targetElement, CSSPropertyWebkitFilter))
+            || (affectsBackdropFilter && attachedAnimation->affects(targetElement, CSSPropertyBackdropFilter)))
             return true;
     }
 
@@ -161,13 +163,14 @@ bool CompositorAnimations::isCompositableProperty(CSSPropertyID property)
     return false;
 }
 
-const CSSPropertyID CompositorAnimations::compositableProperties[6] = {
+const CSSPropertyID CompositorAnimations::compositableProperties[7] = {
     CSSPropertyOpacity,
     CSSPropertyRotate,
     CSSPropertyScale,
     CSSPropertyTransform,
     CSSPropertyTranslate,
-    CSSPropertyWebkitFilter
+    CSSPropertyWebkitFilter,
+    CSSPropertyBackdropFilter
 };
 
 bool CompositorAnimations::getAnimatedBoundingBox(FloatBox& box, const EffectModel& effect, double minValue, double maxValue) const
@@ -271,7 +274,8 @@ bool CompositorAnimations::isCandidateForAnimationOnCompositor(const Timing& tim
                 if (toAnimatableTransform(keyframe->getAnimatableValue().get())->transformOperations().dependsOnBoxSize())
                     return false;
                 break;
-            case CSSPropertyWebkitFilter: {
+            case CSSPropertyWebkitFilter:
+            case CSSPropertyBackdropFilter: {
                 const FilterOperations& operations = toAnimatableFilterOperations(keyframe->getAnimatableValue().get())->operations();
                 if (operations.hasFilterThatMovesPixels())
                     return false;
@@ -301,8 +305,9 @@ bool CompositorAnimations::isCandidateForAnimationOnCompositor(const Timing& tim
 void CompositorAnimations::cancelIncompatibleAnimationsOnCompositor(const Element& targetElement, const Animation& animationToAdd, const EffectModel& effectToAdd)
 {
     const bool affectsOpacity = effectToAdd.affects(PropertyHandle(CSSPropertyOpacity));
-    const bool affectsTransform =  effectToAdd.isTransformRelatedEffect();
+    const bool affectsTransform = effectToAdd.isTransformRelatedEffect();
     const bool affectsFilter = effectToAdd.affects(PropertyHandle(CSSPropertyWebkitFilter));
+    const bool affectsBackdropFilter = effectToAdd.affects(PropertyHandle(CSSPropertyBackdropFilter));
 
     if (!targetElement.hasAnimations())
         return;
@@ -317,7 +322,8 @@ void CompositorAnimations::cancelIncompatibleAnimationsOnCompositor(const Elemen
 
         if ((affectsOpacity && attachedAnimation->affects(targetElement, CSSPropertyOpacity))
             || (affectsTransform && isTransformRelatedAnimation(targetElement, attachedAnimation))
-            || (affectsFilter && attachedAnimation->affects(targetElement, CSSPropertyWebkitFilter)))
+            || (affectsFilter && attachedAnimation->affects(targetElement, CSSPropertyWebkitFilter))
+            || (affectsBackdropFilter && attachedAnimation->affects(targetElement, CSSPropertyBackdropFilter)))
             attachedAnimation->cancelAnimationOnCompositor();
     }
 }
@@ -680,7 +686,8 @@ void CompositorAnimationsImpl::getAnimationOnCompositor(const Timing& timing, in
             curve = adoptPtr(floatCurve);
             break;
         }
-        case CSSPropertyWebkitFilter: {
+        case CSSPropertyWebkitFilter:
+        case CSSPropertyBackdropFilter: {
             targetProperty = WebCompositorAnimation::TargetPropertyFilter;
             WebFilterAnimationCurve* filterCurve = Platform::current()->compositorSupport()->createFilterAnimationCurve();
             addKeyframesToCurve(*filterCurve, values, timing);