Add missing include guards in Cocoa code.

chrome/browser/ui/cocoa/bookmarks/bookmark_bar_view_cocoa.h

 // Copyright (c) 2010 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.
-//
-// A simple custom NSView for the bookmark bar used to prevent clicking and
-// dragging from moving the browser window.
 
 #ifndef CHROME_BROWSER_UI_COCOA_BOOKMARKS_BOOKMARK_BAR_VIEW_COCOA_H_
 #define CHROME_BROWSER_UI_COCOA_BOOKMARKS_BOOKMARK_BAR_VIEW_COCOA_H_
 
 #import <Cocoa/Cocoa.h>
 
 #include "base/mac/scoped_nsobject.h"
 
 @class BookmarkBarController;
 
@@ skipping 12 matching lines @@
 - (NSView*)noItemContainer;
 
 - (instancetype)initWithController:(BookmarkBarController*)controller
                              frame:(NSRect)frame;
 - (void)registerForNotificationsAndDraggedTypes;
 
 // Exposed so the controller can nil itself out.
 @property(nonatomic, assign) BookmarkBarController* controller;
 @end
 
+// A simple custom NSView for the bookmark bar used to prevent clicking and
+// dragging from moving the browser window.
 @interface BookmarkBarView()  // TestingOrInternalAPI
 @property(nonatomic, readonly) BOOL dropIndicatorShown;
 @property(nonatomic, readonly) CGFloat dropIndicatorPosition;
 @end
 
 #endif  // CHROME_BROWSER_UI_COCOA_BOOKMARKS_BOOKMARK_BAR_VIEW_COCOA_H_