Deliver IPC messages together with SwapCompositorFrame

content/renderer/render_widget.h

Index: content/renderer/render_widget.h
diff --git a/content/renderer/render_widget.h b/content/renderer/render_widget.h
index fb6c362155fbdf0629fe331e305d459ef864d145..a674b89221abb85000aeef7ee73480578f27201b 100644
--- a/content/renderer/render_widget.h
+++ b/content/renderer/render_widget.h
@@ -10,6 +10,7 @@
 
 #include "base/auto_reset.h"
 #include "base/basictypes.h"
+#include "base/callback.h"
 #include "base/compiler_specific.h"
 #include "base/memory/ref_counted.h"
 #include "base/memory/scoped_ptr.h"
@@ -21,6 +22,7 @@
 #include "content/common/cursors/webcursor.h"
 #include "content/common/gpu/client/webgraphicscontext3d_command_buffer_impl.h"
 #include "content/common/input/synthetic_gesture_params.h"
+#include "content/renderer/message_delivery_policy.h"
 #include "ipc/ipc_listener.h"
 #include "ipc/ipc_sender.h"
 #include "third_party/WebKit/public/platform/WebRect.h"
@@ -67,6 +69,7 @@ class Range;
 
 namespace content {
 class ExternalPopupMenu;
+class FrameSwapMessageQueue;
 class PepperPluginInstanceImpl;
 class RenderFrameImpl;
 class RenderWidgetCompositor;
@@ -191,6 +194,13 @@ class CONTENT_EXPORT RenderWidget
   // Notifies about a compositor frame commit operation having finished.
   virtual void DidCommitCompositorFrame();
 
+  // Deliveres |message| together with compositor state change updates. The
+  // exact behavior depends on |policy|.
+  //
+  // |msg| message to send, ownership of |msg| is transferred.
+  // |policy| see the comment on MessageDeliveryPolicy.
+  void QueueMessage(IPC::Message* msg, MessageDeliveryPolicy policy);
+
   // Handle common setup/teardown for handling IME events.
   void StartHandlingImeEvent();
   void FinishHandlingImeEvent();
@@ -690,6 +700,7 @@ class CONTENT_EXPORT RenderWidget
   gfx::Point popup_screen_origin_for_emulation_;
   float popup_origin_scale_for_emulation_;
 
+  scoped_refptr<FrameSwapMessageQueue> frame_swap_message_queue_;
   scoped_ptr<ResizingModeSelector> resizing_mode_selector_;
 
   // Lists of swapped out RenderFrames that need to be notified