cc: Make separate interface for BeginFrame ipc from OutputSurface

content/renderer/gpu/render_widget_compositor.cc

Index: content/renderer/gpu/render_widget_compositor.cc
diff --git a/content/renderer/gpu/render_widget_compositor.cc b/content/renderer/gpu/render_widget_compositor.cc
index e5b3c176743468673df740999503a40e03793a3d..e4d415b8c632c8078637c5c614e87273be916053 100644
--- a/content/renderer/gpu/render_widget_compositor.cc
+++ b/content/renderer/gpu/render_widget_compositor.cc
@@ -33,6 +33,7 @@
 #include "content/common/content_switches_internal.h"
 #include "content/common/gpu/client/context_provider_command_buffer.h"
 #include "content/public/common/content_switches.h"
+#include "content/renderer/gpu/compositor_external_begin_frame_source.h"
 #include "content/renderer/input/input_handler_manager.h"
 #include "content/renderer/render_thread_impl.h"
 #include "gpu/command_buffer/client/gles2_interface.h"
@@ -538,6 +539,11 @@ void RenderWidgetCompositor::Initialize(cc::LayerTreeSettings settings) {
     main_thread_compositor_task_runner =
         render_thread->main_thread_compositor_task_runner();
   }
+  scoped_refptr<CompositorExternalBeginFrameSource> external_begin_frame_source;
+  if (settings.begin_frame_scheduling_enabled) {
+    external_begin_frame_source = new CompositorExternalBeginFrameSource(
+                                          widget_->routing_id());

[piman, 2014/10/15 03:34:50]

If both the CompositorExternalBeginFrameSource and the CompositorOutputSurface
have the same routing_id, they will stomp on each other (ForwardingMessageFilter
expects a single handler per routing id). Either you need to have a single
handler and have both the CompositorExternalBeginFrameSource and the
CompositorOutputSurface register to it, or change ForwardingMessageFilter to use
a multimap instead of a map.

[simonhong, 2014/10/15 06:45:14]

Many thanks for this.
I didn't know about it.
I modified ForwardingMessagerFilter to use a multimap.

+  }
   if (compositor_message_loop_proxy.get()) {
     layer_tree_host_ =
         cc::LayerTreeHost::CreateThreaded(this,
@@ -545,7 +551,8 @@ void RenderWidgetCompositor::Initialize(cc::LayerTreeSettings settings) {
                                           gpu_memory_buffer_manager,
                                           settings,
                                           main_thread_compositor_task_runner,
-                                          compositor_message_loop_proxy);
+                                          compositor_message_loop_proxy,
+                                          external_begin_frame_source);
   } else {
     layer_tree_host_ = cc::LayerTreeHost::CreateSingleThreaded(
         this,
@@ -553,7 +560,8 @@ void RenderWidgetCompositor::Initialize(cc::LayerTreeSettings settings) {
         shared_bitmap_manager,
         gpu_memory_buffer_manager,
         settings,
-        main_thread_compositor_task_runner);
+        main_thread_compositor_task_runner,
+        external_begin_frame_source);
   }
   DCHECK(layer_tree_host_);
 }