Fix transparent crack at top of page while resizing devtools NSSplitView divider.

chrome/browser/ui/cocoa/bookmarks/bookmark_bar_controller.mm

 // 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.
 
 #import "chrome/browser/ui/cocoa/bookmarks/bookmark_bar_controller.h"
 
 #include "base/mac/bundle_locations.h"
 #include "base/mac/mac_util.h"
 #include "base/metrics/histogram.h"
 #include "base/sys_string_conversions.h"
@@ skipping 294 matching lines @@
   }
   if (node->parent() == bookmarkModel_->bookmark_bar_node()) {
     [offTheSideButton_ setIsContinuousPulsing:doPulse];
     return;
   }
 
   NOTREACHED() << "no bookmark button found to pulse!";
 }
 
 - (void)dealloc {
+  // Clear delegate so it doesn't get called during stopAnimation.
+  [[self animatableView] setResizeDelegate:nil];
+
   // We better stop any in-flight animation if we're being killed.
   [[self animatableView] stopAnimation];
 
   // Remove our view from its superview so it doesn't attempt to reference
   // it when the controller is gone.
   //TODO(dmaclach): Remove -- http://crbug.com/25845
   [[self view] removeFromSuperview];
 
   // Be sure there is no dangling pointer.
   if ([[self view] respondsToSelector:@selector(setController:)])
@@ skipping 2459 matching lines @@
 // to minimize touching the object passed in (likely a mock).
 - (void)setButtonContextMenu:(id)menu {
   buttonContextMenu_ = menu;
 }
 
 - (void)setIgnoreAnimations:(BOOL)ignore {
   ignoreAnimations_ = ignore;
 }
 
 @end