Use inner HWND for accelerated rendering on windows

chrome/browser/gpu_process_host.cc

Index: chrome/browser/gpu_process_host.cc
===================================================================
--- chrome/browser/gpu_process_host.cc	(revision 67491)
+++ chrome/browser/gpu_process_host.cc	(working copy)
@@ -177,6 +177,9 @@
                         OnAcceleratedSurfaceSetIOSurface)
     IPC_MESSAGE_HANDLER(GpuHostMsg_AcceleratedSurfaceBuffersSwapped,
                         OnAcceleratedSurfaceBuffersSwapped)
+#elif defined(OS_WIN)
+    IPC_MESSAGE_HANDLER_DELAY_REPLY(GpuHostMsg_CreateCompositorHostWindow,
+                                    OnCreateCompositorHostWindow)
 #endif
     // If the IO thread does not handle the message then automatically route it
     // to the UI thread. The UI thread will report an error if it does not
@@ -305,8 +308,8 @@
 class BuffersSwappedDispatcher : public Task {
  public:
   BuffersSwappedDispatcher(
-      int32 renderer_id,
-      int32 render_view_id,
+      int renderer_id,
+      int render_view_id,
       gfx::PluginWindowHandle window,
       uint64 surface_id,
       int32 route_id,
@@ -338,8 +341,8 @@
   }
 
  private:
-  int32 renderer_id_;
-  int32 render_view_id_;
+  int renderer_id_;
+  int render_view_id_;
   gfx::PluginWindowHandle window_;
   uint64 surface_id_;
   int32 route_id_;
@@ -366,6 +369,47 @@
           params.route_id,
           params.swap_buffers_count));
 }
+
+#elif defined(OS_WIN)
+
+namespace {
+
+void SendDelayedReply(IPC::Message* reply_msg) {
+  GpuProcessHost::Get()->Send(reply_msg);
+}
+
+void CreateCompositorHostWindowDispatcher(
+    int renderer_id,
+    int render_view_id,
+    IPC::Message* reply_msg) {
+  RenderViewHost* host = RenderViewHost::FromID(renderer_id,
+                                                render_view_id);
+  if (!host) {
+    return;
+  }
+
+  RenderWidgetHostView* view = host->view();
+  gfx::PluginWindowHandle id = view->CreateCompositorHostWindow();
+
+
+  GpuHostMsg_CreateCompositorHostWindow::WriteReplyParams(reply_msg, id);
+  BrowserThread::PostTask(
+    BrowserThread::IO, FROM_HERE,
+    NewRunnableFunction(&SendDelayedReply, reply_msg));
+}
+
+}  // namespace
+
+void GpuProcessHost::OnCreateCompositorHostWindow(
+    int renderer_id,
+    int render_view_id,
+    IPC::Message* reply_message) {
+  BrowserThread::PostTask(
+      BrowserThread::UI, FROM_HERE,
+      NewRunnableFunction(&CreateCompositorHostWindowDispatcher,
+          renderer_id, render_view_id, reply_message));
+}
+
 #endif
 
 void GpuProcessHost::SendEstablishChannelReply(