[Mac] Remove bookmark bar NIB

chrome/browser/ui/cocoa/bookmarks/bookmark_bar_toolbar_view.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.
 
 // The BookmarkBarToolbarView is responsible for drawing the background of the
 // BookmarkBar's toolbar in either of its two display modes - permanently
 // attached (slimline with a stroke at the bottom edge) or New Tab Page style
 // (padded with a round rect border and the New Tab Page theme behind).
 
 #ifndef CHROME_BROWSER_UI_COCOA_BOOKMARKS_BOOKMARK_BAR_TOOLBAR_VIEW_H_
@@ skipping 14 matching lines @@
 // background image is joined.
 - (int)currentTabContentsHeight;
 
 // Current profile.
 - (Profile*)profile;
 
 @end
 
 @interface BookmarkBarToolbarView : AnimatableView {
  @private
-   // The controller which tells us how we should be drawing (as normal or as a
-   // floating bar).
-   IBOutlet id<BookmarkBarToolbarViewController> controller_;
+  // The controller which tells us how we should be drawing (as normal or as a
+  // floating bar). Weak reference.
+  id<BookmarkBarToolbarViewController> controller_;
 }
+
+// Exposed so that the controller can nil itself out
+- (void)setController:(id<BookmarkBarToolbarViewController>)controller;
 @end
 
 #endif  // CHROME_BROWSER_UI_COCOA_BOOKMARKS_BOOKMARK_BAR_TOOLBAR_VIEW_H_