cc: Delay start of scrollbar animation setNeedsRedraw.

cc/thread_proxy.cc

 // Copyright 2011 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "cc/thread_proxy.h"
 
 #include "base/auto_reset.h"
 #include "base/bind.h"
 #include "base/debug/trace_event.h"
 #include "cc/context_provider.h"
@@ skipping 1217 matching lines @@
 }
 
 void ThreadProxy::renewTreePriorityOnImplThread()
 {
     DCHECK(m_renewTreePriorityOnImplThreadPending);
     m_renewTreePriorityOnImplThreadPending = false;
 
     RenewTreePriority();
 }
 
+void ThreadProxy::RequestScrollbarAnimationOnImplThread(double delay) {
+  Proxy::ImplThread()->postDelayedTask(
+      base::Bind(&ThreadProxy::StartScrollbarAnimationOnImplThread,
+                 m_implThreadWeakPtr),
+      delay * 1000.0);
+}
+
+void ThreadProxy::StartScrollbarAnimationOnImplThread() {
+  m_layerTreeHostImpl->StartScrollbarAnimation(base::TimeTicks::Now());
+}
+
 }  // namespace cc