ui: Cleanup class/struct forward declarations

ui/chromeos/touch_exploration_controller.h

 // 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.
 
 #ifndef UI_CHROMEOS_TOUCH_EXPLORATION_CONTROLLER_H_
 #define UI_CHROMEOS_TOUCH_EXPLORATION_CONTROLLER_H_
 
 #include "base/macros.h"
 #include "base/timer/timer.h"
 #include "base/values.h"
 #include "ui/accessibility/ax_enums.h"
 #include "ui/chromeos/ui_chromeos_export.h"
 #include "ui/events/event.h"
 #include "ui/events/event_rewriter.h"
 #include "ui/events/gesture_detection/gesture_detector.h"
 #include "ui/events/gestures/gesture_provider_aura.h"
 #include "ui/gfx/geometry/point.h"
 
 namespace aura {
 class Window;
 }
 
 namespace ui {
 
 class Event;
-class EventHandler;
 class GestureEvent;
 class GestureProviderAura;
 class TouchEvent;
 
 // A delegate to handle commands in response to detected accessibility gesture
 // events.
 class TouchExplorationControllerDelegate {
  public:
   virtual ~TouchExplorationControllerDelegate() {}
 
@@ skipping 469 matching lines @@
 
   // LocatedEvents within this area should be left alone.
   gfx::Rect exclude_bounds_;
 
   DISALLOW_COPY_AND_ASSIGN(TouchExplorationController);
 };
 
 }  // namespace ui
 
 #endif  // UI_CHROMEOS_TOUCH_EXPLORATION_CONTROLLER_H_