Wire input events through the ViewManagerClient interface.

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

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 import "../geometry/geometry.mojom"
+import "../input_events/input_events.mojom"
 
 module mojo.view_manager {
 
 struct INode {
   uint32 parent_id;
   uint32 node_id;
   uint32 view_id;
   mojo.Rect bounds;
 };
 
@@ skipping 115 matching lines @@
 
   // Invoked when a node is deleted.
   OnNodeDeleted(uint32 node, uint32 server_change_id);
 
   // Invoked when the view associated with a node is replaced by another view.
   // 0 is used to identify a null view.
   OnNodeViewReplaced(uint32 node, uint32 new_view_id, uint32 old_view_id);
 
   // 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) => ();
 };
 
 }