Fix issues related to a continuous event getting coalesced with a discrete event.

content/common/input/input_event_dispatch_type.h

Index: content/common/input/input_event_dispatch_type.h
diff --git a/content/common/input/input_event_dispatch_type.h b/content/common/input/input_event_dispatch_type.h
index 5f3234c30386ae2fab97b108cef2430ec2a7d87e..ea802ff2c811e1ed32d55a8d32791035eec3b8b7 100644
--- a/content/common/input/input_event_dispatch_type.h
+++ b/content/common/input/input_event_dispatch_type.h
@@ -15,7 +15,10 @@ enum InputEventDispatchType {
   DISPATCH_TYPE_BLOCKING_NOTIFY_MAIN,
   // Dispatch a non-blocking event. Sender will not receive an ACK.
   DISPATCH_TYPE_NON_BLOCKING,
-  DISPATCH_TYPE_MAX = DISPATCH_TYPE_NON_BLOCKING
+  // Dispatch a non-blocking event and notify main thread as well. This type
+  // should only be sent from the compositor to main thread.
+  DISPATCH_TYPE_NON_BLOCKING_NOTIFY_MAIN,
+  DISPATCH_TYPE_MAX = DISPATCH_TYPE_NON_BLOCKING_NOTIFY_MAIN
 };
 
 }  // namespace content