Activate LayerImpl tree with sync+push instead of pointer swap

cc/heads_up_display_layer_impl.cc

 // Copyright 2012 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/heads_up_display_layer_impl.h"
 
 #include <limits>
 
 #include "base/stringprintf.h"
 #include "cc/debug_colors.h"
@@ skipping 42 matching lines @@
     , m_averageFPS(0)
     , m_minFPS(0)
     , m_maxFPS(0)
 {
 }
 
 HeadsUpDisplayLayerImpl::~HeadsUpDisplayLayerImpl()
 {
 }
 
+scoped_ptr<LayerImpl> HeadsUpDisplayLayerImpl::createLayerImpl(LayerTreeImpl* treeImpl)
+{
+    return HeadsUpDisplayLayerImpl::create(treeImpl, id()).PassAs<LayerImpl>();
+}
+
+void HeadsUpDisplayLayerImpl::pushPropertiesTo(LayerImpl* layerImpl)
+{
+    LayerImpl::pushPropertiesTo(layerImpl);
+
+    if (!m_fontAtlas)
+        return;
+
+    HeadsUpDisplayLayerImpl* hudLayerImpl = static_cast<HeadsUpDisplayLayerImpl*>(layerImpl);
+    hudLayerImpl->setFontAtlas(m_fontAtlas.Pass());
+}
+
 void HeadsUpDisplayLayerImpl::setFontAtlas(scoped_ptr<FontAtlas> fontAtlas)
 {
     m_fontAtlas = fontAtlas.Pass();
 }
 
 void HeadsUpDisplayLayerImpl::willDraw(ResourceProvider* resourceProvider)
 {
     LayerImpl::willDraw(resourceProvider);
 
     if (!m_hudTexture)
@@ skipping 312 matching lines @@
 
     canvas->restore();
 }
 
 const char* HeadsUpDisplayLayerImpl::layerTypeAsString() const
 {
     return "HeadsUpDisplayLayer";
 }
 
 }  // namespace cc