Move ZoomObserver, ZoomController and ZoomEventManager to components/.

components/ui/zoom/zoom_observer.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 CHROME_BROWSER_UI_ZOOM_ZOOM_OBSERVER_H_
-#define CHROME_BROWSER_UI_ZOOM_ZOOM_OBSERVER_H_
+#ifndef COMPONENTS_UI_ZOOM_ZOOM_OBSERVER_H_
+#define COMPONENTS_UI_ZOOM_ZOOM_OBSERVER_H_
 
-#include "chrome/browser/ui/zoom/zoom_controller.h"
+#include "components/ui/zoom/zoom_controller.h"
 
-namespace content {
-class WebContents;
-}
+namespace ui_zoom {
 
 // Interface for objects that wish to be notified of changes in ZoomController.
 class ZoomObserver {
  public:
   // Notification that the zoom percentage has changed.
   virtual void OnZoomChanged(const ZoomController::ZoomChangedEventData& data) {
   }
 
  protected:
   virtual ~ZoomObserver() {}
 };
 
-#endif  // CHROME_BROWSER_UI_ZOOM_ZOOM_OBSERVER_H_
+}  // namespace ui_zoom
+
+#endif  // COMPONENTS_UI_ZOOM_ZOOM_OBSERVER_H_