[Mac] Inform reference counted objects that hold a weak Browser* when the Browser is being destroye…

chrome/browser/ui/cocoa/extensions/browser_actions_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/extensions/browser_actions_controller.h"
 
 #include <string>
 
 #include "base/strings/sys_string_conversions.h"
 #include "chrome/browser/extensions/extension_message_bubble_controller.h"
@@ skipping 376 matching lines @@
                object:containerView_];
     }
 
     focusedViewIndex_ = -1;
   }
 
   return self;
 }
 
 - (void)dealloc {
+  [self browserWillBeDestroyed];
+  [super dealloc];
+}
+
+- (void)browserWillBeDestroyed {
+  [overflowMenu_ setDelegate:nil];
   // Explicitly destroy the ToolbarActionsBar so all buttons get removed with a
   // valid BrowserActionsController, and so we can verify state before
   // destruction.
-  toolbarActionsBar_->DeleteActions();
-  toolbarActionsBar_.reset();
+  if (toolbarActionsBar_.get()) {
+    toolbarActionsBar_->DeleteActions();
+    toolbarActionsBar_.reset();
+  }
   DCHECK_EQ(0u, [buttons_ count]);
   [[NSNotificationCenter defaultCenter] removeObserver:self];
-  [super dealloc];
+  browser_ = nullptr;
 }
 
 - (void)update {
   toolbarActionsBar_->Update();
 }
 
 - (NSUInteger)buttonCount {
   return [buttons_ count];
 }
 
@@ skipping 612 matching lines @@
 }
 
 #pragma mark -
 #pragma mark Testing Methods
 
 - (BrowserActionButton*)buttonWithIndex:(NSUInteger)index {
   return index < [buttons_ count] ? [buttons_ objectAtIndex:index] : nil;
 }
 
 @end