Use input events to improve vsync scheduling

cc/layer_tree_host_impl.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/layer_tree_host_impl.h"
 
 #include <algorithm>
 
 #include "base/basictypes.h"
 #include "base/debug/trace_event.h"
@@ skipping 763 matching lines @@
 
     // TODO(piman): We may need to do some validation on this ack before processing it.
     m_renderer->receiveCompositorFrameAck(ack);
 }
 
 void LayerTreeHostImpl::DidVSync(base::TimeTicks frameTime)
 {
     m_client->didVSync(frameTime);
 }
 
+void LayerTreeHostImpl::didReceiveLastInputEventForVSync()
+{
+    m_client->didReceiveLastInputEventForVSync();
+}
+
 void LayerTreeHostImpl::OnCanDrawStateChangedForTree(LayerTreeImpl*)
 {
     m_client->onCanDrawStateChanged(canDraw());
 }
 
 CompositorFrameMetadata LayerTreeHostImpl::makeCompositorFrameMetadata() const
 {
     if (!rootScrollLayer())
         return CompositorFrameMetadata();
 
@@ skipping 862 matching lines @@
 }
 
 skia::RefPtr<SkPicture> LayerTreeHostImpl::capturePicture()
 {
     LayerTreeImpl* tree = pendingTree() ? pendingTree() : activeTree();
     LayerImpl* layer = getNonCompositedContentLayerRecursive(tree->RootLayer());
     return layer ? layer->getPicture() : skia::RefPtr<SkPicture>();
 }
 
 }  // namespace cc