Move //components/ui/zoom to top-level under //components

components/ui/zoom/zoom_event_manager_observer.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 COMPONENTS_UI_ZOOM_ZOOM_EVENT_MANAGER_OBSERVER_H_
-#define COMPONENTS_UI_ZOOM_ZOOM_EVENT_MANAGER_OBSERVER_H_
-
-namespace ui_zoom {
-
-class ZoomEventManagerObserver {
- public:
-  // TODO(wjmaclean): convert existing ZoomLevelChangedCallbacks to be
-  // observers.
-  virtual void OnZoomLevelChanged() {}
-  virtual void OnDefaultZoomLevelChanged() {}
-
- protected:
-  virtual ~ZoomEventManagerObserver() {}
-};
-
-}  // namespace ui_zoom
-
-#endif  // COMPONENTS_UI_ZOOM_ZOOM_EVENT_MANAGER_OBSERVER_H_