Schedule bitmap animation timers on the compositor task runner.

third_party/WebKit/Source/core/dom/TaskRunnerHelper.cpp

Index: third_party/WebKit/Source/core/dom/TaskRunnerHelper.cpp
diff --git a/third_party/WebKit/Source/core/dom/TaskRunnerHelper.cpp b/third_party/WebKit/Source/core/dom/TaskRunnerHelper.cpp
index 631c5de8c0ec7a26c67b96aea14956e1c38bf507..42bfd3b2f8015b8ae1e56a997760e344d0416a47 100644
--- a/third_party/WebKit/Source/core/dom/TaskRunnerHelper.cpp
+++ b/third_party/WebKit/Source/core/dom/TaskRunnerHelper.cpp
@@ -34,6 +34,9 @@ RefPtr<WebTaskRunner> TaskRunnerHelper::Get(TaskType type, LocalFrame* frame) {
     case TaskType::kDatabaseAccess:
       return frame ? frame->FrameScheduler()->SuspendableTaskRunner()
                    : Platform::Current()->CurrentThread()->GetWebTaskRunner();
+    case TaskType::kAnimationTimer:
+      return frame ? frame->FrameScheduler()->CompositorTaskRunner()
+                   : Platform::Current()->CurrentThread()->GetWebTaskRunner();
     case TaskType::kDOMManipulation:
     case TaskType::kUserInteraction:
     case TaskType::kHistoryTraversal:
@@ -116,6 +119,7 @@ RefPtr<WebTaskRunner> TaskRunnerHelper::Get(TaskType type,
     case TaskType::kMiscPlatformAPI:
     case TaskType::kUnspecedTimer:
     case TaskType::kUnspecedLoading:
+    case TaskType::kAnimationTimer:
     case TaskType::kUnthrottled:
       // UnthrottledTaskRunner is generally discouraged in future.
       // TODO(nhiroki): Identify which tasks can be throttled / suspendable and