Teach main thread event queue about closures.

content/renderer/input/input_event_filter.h

Index: content/renderer/input/input_event_filter.h
diff --git a/content/renderer/input/input_event_filter.h b/content/renderer/input/input_event_filter.h
index 939e723d25f5a18d5e6cb649c3691cba254aac63..09bcb5b83a0a6ffdd66830ced8e578e515081ddf 100644
--- a/content/renderer/input/input_event_filter.h
+++ b/content/renderer/input/input_event_filter.h
@@ -63,6 +63,11 @@ class CONTENT_EXPORT InputEventFilter : public InputHandlerManagerClient,
   void SetInputHandlerManager(InputHandlerManager*) override;
   void RegisterRoutingID(int routing_id) override;
   void UnregisterRoutingID(int routing_id) override;
+  void AssociateRenderFrameRoutingID(int render_frame_routing_id,
+                                     int render_view_routing_id) override;
+  void QueueClosureForMainThreadEventQueue(
+      int routing_id,
+      const base::Closure& closure) override;
   void DidOverscroll(int routing_id,
                      const ui::DidOverscrollParams& params) override;
   void DidStopFlinging(int routing_id) override;
@@ -102,7 +107,8 @@ class CONTENT_EXPORT InputEventFilter : public InputHandlerManagerClient,
  private:
   ~InputEventFilter() override;
 
-  void ForwardToHandler(const IPC::Message& message,
+  void ForwardToHandler(int routing_id,
+                        const IPC::Message& message,
                         base::TimeTicks received_time);
   void DidForwardToHandlerAndOverscroll(
       int routing_id,
@@ -136,6 +142,9 @@ class CONTENT_EXPORT InputEventFilter : public InputHandlerManagerClient,
       std::unordered_map<int, scoped_refptr<MainThreadEventQueue>>;
   RouteQueueMap route_queues_;
 
+  using AssociatedRoutes = std::unordered_map<int, int>;
+  AssociatedRoutes associated_routes_;
+
   blink::scheduler::RendererScheduler* renderer_scheduler_;
 };