RenderWidget popup should be a NSWindow so it can go outside the main window.

chrome/browser/ui/cocoa/bookmarks/bookmark_bar_controller.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_COCOA_BOOKMARKS_BOOKMARK_BAR_CONTROLLER_H_
 #define CHROME_BROWSER_UI_COCOA_BOOKMARKS_BOOKMARK_BAR_CONTROLLER_H_
 
 #import <Cocoa/Cocoa.h>
 #include <map>
 
@@ skipping 131 matching lines @@
 
 @end
 
 // A controller for the bookmark bar in the browser window. Handles showing
 // and hiding based on the preference in the given profile.
 @interface BookmarkBarController :
     NSViewController<BookmarkBarState,
                      BookmarkBarToolbarViewController,
                      BookmarkButtonDelegate,
                      BookmarkButtonControllerProtocol,
-                     CrApplicationEventHookProtocol,
+                     CrEventHookProtocol,
                      NSUserInterfaceValidations,
                      NSDraggingDestination> {
  @private
   // The state of the bookmark bar. If an animation is running, this is set to
   // the "destination" and |lastState_| is set to the "original" state.
   BookmarkBar::State state_;
 
   // The "original" state of the bookmark bar if an animation is running.
   BookmarkBar::State lastState_;
 
@@ skipping 244 matching lines @@
 
 // The following are for testing purposes only and are not used internally.
 - (NSMenu *)menuForFolderNode:(const BookmarkNode*)node;
 - (NSMenu*)buttonContextMenu;
 - (void)setButtonContextMenu:(id)menu;
 // Set to YES in order to prevent animations.
 - (void)setIgnoreAnimations:(BOOL)ignore;
 @end
 
 #endif  // CHROME_BROWSER_UI_COCOA_BOOKMARKS_BOOKMARK_BAR_CONTROLLER_H_