Change the non-blocking event queue to the main thread event queue.

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 e4acb4c1cee93f8760d801ae2dc684fcf4b43a9d..ea802ff2c811e1ed32d55a8d32791035eec3b8b7 100644
--- a/content/common/input/input_event_dispatch_type.h
+++ b/content/common/input/input_event_dispatch_type.h
@@ -8,9 +8,17 @@
 namespace content {
 
 enum InputEventDispatchType {
-  DISPATCH_TYPE_NORMAL,        // Dispatch a normal event.
-  DISPATCH_TYPE_NON_BLOCKING,  // Dispatch a non-blocking event.
-  DISPATCH_TYPE_MAX = DISPATCH_TYPE_NON_BLOCKING
+  // Dispatch a blocking event. Sender is waiting on an ACK.
+  DISPATCH_TYPE_BLOCKING,
+  // Dispatch a blocking event and notify main thread as well. This type
+  // should only be sent from the compositor to main thread.
+  DISPATCH_TYPE_BLOCKING_NOTIFY_MAIN,
+  // Dispatch a non-blocking event. Sender will not receive an ACK.
+  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