cc : Stop pushing layers from hidden subtrees at commit

cc/layers/surface_layer.cc

 // Copyright 2014 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/surface_layer.h"
 
 #include <stdint.h>
 
 #include "base/macros.h"
 #include "base/memory/ptr_util.h"
@@ skipping 101 matching lines @@
       primary_reference_returner_ = ref_factory_->CreateReference(
           layer_tree_host(), primary_surface_info_.id());
     }
     if (fallback_surface_info_.is_valid()) {
       fallback_reference_returner_ = ref_factory_->CreateReference(
           layer_tree_host(), fallback_surface_info_.id());
     }
   }
 }
 
+bool SurfaceLayer::IsSurfaceLayer() const {
+  return true;
+}
+
 void SurfaceLayer::PushPropertiesTo(LayerImpl* layer) {
   Layer::PushPropertiesTo(layer);
   TRACE_EVENT0("cc", "SurfaceLayer::PushPropertiesTo");
   SurfaceLayerImpl* layer_impl = static_cast<SurfaceLayerImpl*>(layer);
   layer_impl->SetPrimarySurfaceInfo(primary_surface_info_);
   layer_impl->SetFallbackSurfaceInfo(fallback_surface_info_);
   layer_impl->SetStretchContentToFillBounds(stretch_content_to_fill_bounds_);
 }
 
+const SurfaceId* SurfaceLayer::GetSurfaceId() const {
+  if (layer_tree_host()->GetSettings().enable_surface_synchronization) {
+    if (fallback_surface_info_.is_valid())
+      return &fallback_surface_info_.id();
+  } else {
+    return &primary_surface_info_.id();
+  }
+  return nullptr;
+}
+
 void SurfaceLayer::RemoveReference(base::Closure reference_returner) {
   if (!reference_returner)
     return;
   auto swap_promise = base::MakeUnique<SatisfySwapPromise>(
       std::move(reference_returner),
       layer_tree_host()->GetTaskRunnerProvider()->MainThreadTaskRunner());
   layer_tree_host()->GetSwapPromiseManager()->QueueSwapPromise(
       std::move(swap_promise));
 }
 
 }  // namespace cc