InputHandlerProxy to inform blink scheduler of input events

content/renderer/input/input_handler_proxy.cc

Index: content/renderer/input/input_handler_proxy.cc
diff --git a/content/renderer/input/input_handler_proxy.cc b/content/renderer/input/input_handler_proxy.cc
index 6970d22003e9b589003fc7eb27bbdeb48ee372c3..90df5cb70e82c70706586ec3e8b07a9baec07abf 100644
--- a/content/renderer/input/input_handler_proxy.cc
+++ b/content/renderer/input/input_handler_proxy.cc
@@ -195,6 +195,7 @@ InputHandlerProxy::EventDisposition InputHandlerProxy::HandleInputEvent(
   TRACE_EVENT1("input", "InputHandlerProxy::HandleInputEvent",
                "type", WebInputEventTraits::GetName(event.type));
 
+  client_->DidReceiveInputEvent();

[jdduke (slow), 2014/09/11 16:29:35]

This method is called internally for synthetic wheel/fling gestures, is it OK
that the client is notified in such cases? Or do we only want it when we receive
an external event? Honestly, this method should be private, but I think
somewhere along the line somebody thought it convenient to keep public for
testing purposes.

[Sami, 2014/09/11 16:42:31]

I think we want to have it called for flings too, since they were still
initiated by the user and count as interacting with the device in my mind.

[alexclarke, 2014/09/11 16:45:00]

Yes I think we do want to treat synthetic events the same, since this should
make the user initiated animation smoother.

[jdduke (slow), 2014/09/11 16:49:11]

sgtm.

   if (FilterInputEventForFlingBoosting(event))
     return DID_HANDLE;