[SPv2] Decomposite otherwise-compositable animations that paint nothing.

third_party/WebKit/Source/core/animation/DocumentAnimations.cpp

Index: third_party/WebKit/Source/core/animation/DocumentAnimations.cpp
diff --git a/third_party/WebKit/Source/core/animation/DocumentAnimations.cpp b/third_party/WebKit/Source/core/animation/DocumentAnimations.cpp
index 806b319ef9dfe6410d657e6e6051e18c27d0295e..0fa700df2445855b2f787a338a3892fd475b5f6b 100644
--- a/third_party/WebKit/Source/core/animation/DocumentAnimations.cpp
+++ b/third_party/WebKit/Source/core/animation/DocumentAnimations.cpp
@@ -67,10 +67,12 @@ void DocumentAnimations::updateAnimationTimingIfNeeded(Document& document) {
 
 void DocumentAnimations::updateAnimations(
     Document& document,
-    DocumentLifecycle::LifecycleState requiredLifecycleState) {
+    DocumentLifecycle::LifecycleState requiredLifecycleState,
+    Optional<CompositorElementIdSet>& compositedAnimationElementIds) {
   DCHECK(document.lifecycle().state() >= requiredLifecycleState);
 
-  if (document.compositorPendingAnimations().update()) {
+  if (document.compositorPendingAnimations().update(
+          compositedAnimationElementIds)) {
     DCHECK(document.view());
     document.view()->scheduleAnimation();
   }