Wire input events through the ViewManagerClient interface.

mojo/services/public/interfaces/view_manager/view_manager.mojom

Index: mojo/services/public/interfaces/view_manager/view_manager.mojom
diff --git a/mojo/services/public/interfaces/view_manager/view_manager.mojom b/mojo/services/public/interfaces/view_manager/view_manager.mojom
index d37b2621eb0c2862edf73571daa77a4f71c7ac4b..817a861f2edd0285d52d60f13ae84c1827446ce3 100644
--- a/mojo/services/public/interfaces/view_manager/view_manager.mojom
+++ b/mojo/services/public/interfaces/view_manager/view_manager.mojom
@@ -3,6 +3,7 @@
 // found in the LICENSE file.
 
 import "../geometry/geometry.mojom"
+import "../input_events/input_events.mojom"
 
 module mojo.view_manager {
 
@@ -147,6 +148,9 @@ interface IViewManagerClient {
 
   // Invoked when a view is deleted.
   OnViewDeleted(uint32 view);
+
+  // Invoked when an event is targeted at the specified view.
+  OnViewInputEvent(uint32 view, mojo.Event event) => ();
 };
 
 }