Mac: Remove ToolbarButtonCell (and associated files).

chrome/browser/cocoa/toolbar_button_cell.h

-// Copyright (c) 2009 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_COCOA_TOOLBAR_BUTTON_CELL_H_
-#define CHROME_BROWSER_COCOA_TOOLBAR_BUTTON_CELL_H_
-
-#import <Cocoa/Cocoa.h>
-#import "chrome/browser/cocoa/clickhold_button_cell.h"
-
-// A button cell for the toolbar.
-
-// TODO(jrg): Why have a class at all when the base class does it all?
-// I anticipate making changes for extensions.  Themes may also
-// require changes.  I don't yet know if those will be common across
-// the toolbar and bookmark bar or not.  The initial CL which made
-// this empty was the use of the base class for both toolbar and
-// bookmark bar button cells.  It seems wasteful to remove the files
-// then add them back in soon after.
-// TODO(jrg): If no differences come up, remove this file and use
-// the base class explicitly for both the toolbar and bookmark bar.
-
-@interface ToolbarButtonCell : ClickHoldButtonCell {
-}
-@end
-
-#endif  // CHROME_BROWSER_COCOA_TOOLBAR_BUTTON_CELL_H_