cros: Remove some OS platform ifdefs from ash

ash/touch/touch_observer_hud.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_TOUCH_TOUCH_OBSERVER_HUD_H_
 #define ASH_TOUCH_TOUCH_OBSERVER_HUD_H_
 
 #include <stdint.h>
 
 #include "ash/ash_export.h"
 #include "ash/display/window_tree_host_manager.h"
 #include "base/macros.h"
 #include "ui/display/display_observer.h"
+#include "ui/display/manager/chromeos/display_configurator.h"
 #include "ui/events/event_handler.h"
 #include "ui/views/widget/widget_observer.h"
 
-#if defined(OS_CHROMEOS)
-#include "ui/display/manager/chromeos/display_configurator.h"
-#endif  // defined(OS_CHROMEOS)
-
 namespace views {
 class Widget;
 }
 
 namespace ash {
 
 // An event filter which handles system level gesture events. Objects of this
 // class manage their own lifetime.
 class ASH_EXPORT TouchObserverHUD
     : public ui::EventHandler,
       public views::WidgetObserver,
       public display::DisplayObserver,
-#if defined(OS_CHROMEOS)
       public display::DisplayConfigurator::Observer,
-#endif  // defined(OS_CHROMEOS)
       public WindowTreeHostManager::Observer {
  public:
   // Called to clear touch points and traces from the screen. Default
   // implementation does nothing. Sub-classes should implement appropriately.
   virtual void Clear();
 
   // Removes the HUD from the screen.
   void Remove();
 
   int64_t display_id() const { return display_id_; }
@@ skipping 15 matching lines @@
 
   // Overridden from views::WidgetObserver.
   void OnWidgetDestroying(views::Widget* widget) override;
 
   // Overridden from display::DisplayObserver.
   void OnDisplayAdded(const display::Display& new_display) override;
   void OnDisplayRemoved(const display::Display& old_display) override;
   void OnDisplayMetricsChanged(const display::Display& display,
                                uint32_t metrics) override;
 
-#if defined(OS_CHROMEOS)
   // Overriden from display::DisplayConfigurator::Observer.
   void OnDisplayModeChanged(
       const display::DisplayConfigurator::DisplayStateList& outputs) override;
-#endif  // defined(OS_CHROMEOS)
 
   // Overriden form WindowTreeHostManager::Observer.
   void OnDisplaysInitialized() override;
   void OnDisplayConfigurationChanging() override;
   void OnDisplayConfigurationChanged() override;
 
  private:
   friend class TouchHudTestBase;
 
   const int64_t display_id_;
   aura::Window* root_window_;
 
   views::Widget* widget_;
 
   DISALLOW_COPY_AND_ASSIGN(TouchObserverHUD);
 };
 
 }  // namespace ash
 
 #endif  // ASH_TOUCH_TOUCH_OBSERVER_HUD_H_