Change explanation string for the Subresource Filter prompt.

chrome/browser/ui/cocoa/content_settings/content_setting_bubble_cocoa.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.
 
 #import <Cocoa/Cocoa.h>
 
 #include <map>
 #include <memory>
 
 #include "base/macros.h"
@@ skipping 35 matching lines @@
   }
 };
 typedef std::map<NSPopUpButton*, MediaMenuParts*, compare_button>
   MediaMenuPartsMap;
 }  // namespace content_setting_bubble
 
 // Manages a "content blocked" bubble.
 @interface ContentSettingBubbleController : BaseBubbleController {
  @private
   IBOutlet NSTextField* titleLabel_;
+  IBOutlet NSTextField* messageLabel_;
   IBOutlet NSMatrix* allowBlockRadioGroup_;
 
   IBOutlet NSButton* manageButton_;
   IBOutlet NSButton* doneButton_;
   IBOutlet NSButton* loadButton_;
 
   // The container for the bubble contents of the geolocation bubble.
   IBOutlet NSView* contentsContainer_;
 
   IBOutlet NSTextField* blockedResourcesField_;
@@ skipping 35 matching lines @@
 - (IBAction)mediaMenuChanged:(id)sender;
 
 @end
 
 @interface ContentSettingBubbleController (TestingAPI)
 
 // Returns the weak reference to the |mediaMenus_|.
 - (content_setting_bubble::MediaMenuPartsMap*)mediaMenus;
 
 @end