WIP: Eliminate event.target() usage from TrayEventFilter

content/renderer/mus/compositor_mus_connection.h

 // Copyright 2015 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.
 
 #ifndef CONTENT_RENDERER_MUS_COMPOSITOR_MUS_CONNECTION_H_
 #define CONTENT_RENDERER_MUS_COMPOSITOR_MUS_CONNECTION_H_
 
 #include "base/bind.h"
 #include "base/compiler_specific.h"
 #include "base/macros.h"
@@ skipping 50 matching lines @@
       std::unique_ptr<blink::WebInputEvent> web_event,
       const base::Callback<void(mus::mojom::EventResult)>& ack);
 
   void OnWindowInputEventAckOnMainThread(
       const base::Callback<void(mus::mojom::EventResult)>& ack,
       mus::mojom::EventResult result);
 
   // WindowTreeDelegate implementation:
   void OnConnectionLost(mus::WindowTreeConnection* connection) override;
   void OnEmbed(mus::Window* root) override;
-  void OnEventObserved(const ui::Event& event) override;
+  void OnEventObserved(const ui::Event& event, mus::Window* target) override;
 
   // InputEventHandler implementation:
   void OnWindowInputEvent(
       mus::Window* window,
       const ui::Event& event,
       std::unique_ptr<base::Callback<void(mus::mojom::EventResult)>>*
           ack_callback) override;
 
   const int routing_id_;
   mus::Window* root_;
   scoped_refptr<base::SingleThreadTaskRunner> main_task_runner_;
   scoped_refptr<base::SingleThreadTaskRunner> compositor_task_runner_;
   InputHandlerManager* const input_handler_manager_;
   std::unique_ptr<mus::WindowSurfaceBinding> window_surface_binding_;
 
   DISALLOW_COPY_AND_ASSIGN(CompositorMusConnection);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_RENDERER_MUS_COMPOSITOR_MUS_CONNECTION_H_