[Mac] Fix for fullscreen toolbar

chrome/browser/ui/cocoa/browser_window_controller.mm

 // Copyright 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/browser_window_controller.h"
 
 #include <cmath>
 #include <numeric>
 #include <utility>
 
@@ skipping 1961 matching lines @@
   DCHECK([self isInAnyFullscreenMode]);
   if (![self isInAnyFullscreenMode])
     return;
 
   NSWindow* window = [self window];
   [window setFrame:[[window screen] frame] display:YES];
   [self layoutSubviews];
 }
 
 - (BOOL)isBarVisibilityLockedForOwner:(id)owner {
-  DCHECK(owner);
   DCHECK(barVisibilityLocks_);
-  return [barVisibilityLocks_ containsObject:owner];
+  return owner ? [barVisibilityLocks_ containsObject:owner]
+               : [barVisibilityLocks_ count];
 }
 
 - (void)lockBarVisibilityForOwner:(id)owner withAnimation:(BOOL)animate {
   if (![self isBarVisibilityLockedForOwner:owner]) {
     [barVisibilityLocks_ addObject:owner];
 
     // If enabled, show the overlay if necessary (and if the fullscreen
     // toolbar is hidden).
     if (barVisibilityUpdatesEnabled_) {
       [fullscreenToolbarController_ ensureOverlayShownWithAnimation:animate];
@@ skipping 55 matching lines @@
 
 - (NSRect)savedRegularWindowFrame {
   return savedRegularWindowFrame_;
 }
 
 - (BOOL)isFullscreenTransitionInProgress {
   return enteringAppKitFullscreen_ || exitingAppKitFullscreen_;
 }
 
 @end  // @implementation BrowserWindowController(WindowType)