Add support for (de)serializing HeadsUpDisplayLayer

cc/layers/heads_up_display_layer.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/layers/heads_up_display_layer.h"
 
 #include <algorithm>
 
 #include "base/trace_event/trace_event.h"
 #include "cc/layers/heads_up_display_layer_impl.h"
+#include "cc/proto/layer.pb.h"
 #include "cc/trees/layer_tree_host.h"
 
 namespace cc {
 
 scoped_refptr<HeadsUpDisplayLayer> HeadsUpDisplayLayer::Create(
     const LayerSettings& settings) {
   return make_scoped_refptr(new HeadsUpDisplayLayer(settings));
 }
 
 HeadsUpDisplayLayer::HeadsUpDisplayLayer(const LayerSettings& settings)
@@ skipping 33 matching lines @@
 
 bool HeadsUpDisplayLayer::HasDrawableContent() const {
   return true;
 }
 
 scoped_ptr<LayerImpl> HeadsUpDisplayLayer::CreateLayerImpl(
     LayerTreeImpl* tree_impl) {
   return HeadsUpDisplayLayerImpl::Create(tree_impl, layer_id_);
 }
 
+void HeadsUpDisplayLayer::SetTypeForProtoSerialization(
+    proto::LayerNode* proto) const {
+  proto->set_type(proto::LayerType::HEADS_UP_DISPLAY_LAYER);
+}
+
 }  // namespace cc