events: Change gesture-event handler in EventHandler to not return any values.

ash/wm/workspace/frame_maximize_button.h

 // Copyright (c) 2012 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 ASH_WM_WORKSPACE_FRAME_MAXIMIZE_BUTTON_H_
 #define ASH_WM_WORKSPACE_FRAME_MAXIMIZE_BUTTON_H_
 
 #include "ash/ash_export.h"
 #include "ash/wm/workspace/maximize_bubble_frame_state.h"
 #include "ash/wm/workspace/snap_types.h"
@@ skipping 48 matching lines @@
 
   // ImageButton overrides:
   virtual bool OnMousePressed(const ui::MouseEvent& event) OVERRIDE;
   virtual void OnMouseEntered(const ui::MouseEvent& event) OVERRIDE;
   virtual void OnMouseExited(const ui::MouseEvent& event) OVERRIDE;
   virtual bool OnMouseDragged(const ui::MouseEvent& event) OVERRIDE;
   virtual void OnMouseReleased(const ui::MouseEvent& event) OVERRIDE;
   virtual void OnMouseCaptureLost() OVERRIDE;
 
   // ui::EventHandler overrides:
-  virtual ui::EventResult OnGestureEvent(ui::GestureEvent* event) OVERRIDE;
+  virtual void OnGestureEvent(ui::GestureEvent* event) OVERRIDE;
 
   // Unit test overwrite: Change the UI delay used for the bubble show up.
   void set_bubble_appearance_delay_ms(int bubble_appearance_delay_ms) {
     bubble_appearance_delay_ms_ = bubble_appearance_delay_ms;
   }
 
   // Unit test accessor for the maximize bubble.
   MaximizeBubbleController* maximizer() { return maximizer_.get(); }
 
   // Unit test to see if phantom window is open.
@@ skipping 84 matching lines @@
 
   // The delay of the bubble appearance.
   int bubble_appearance_delay_ms_;
 
   DISALLOW_COPY_AND_ASSIGN(FrameMaximizeButton);
 };
 
 }  // namespace ash
 
 #endif  // ASH_WM_WORKSPACE_FRAME_MAXIMIZE_BUTTON_H_