Cleanup: Use content::kAboutBlankURL instead of the raw string in contents/.

content/shell/shell_application_mac.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.
 
 #include "content/shell/shell_application_mac.h"
 
 #include "base/auto_reset.h"
+#include "content/public/common/url_constants.h"
 #include "content/shell/shell.h"
 #include "content/shell/shell_browser_context.h"
 #include "content/shell/shell_content_browser_client.h"
 #include "url/gurl.h"
 
 @implementation ShellCrApplication
 
 - (BOOL)isHandlingSendEvent {
   return handlingSendEvent_;
 }
 
 - (void)sendEvent:(NSEvent*)event {
   base::AutoReset<BOOL> scoper(&handlingSendEvent_, YES);
   [super sendEvent:event];
 }
 
 - (void)setHandlingSendEvent:(BOOL)handlingSendEvent {
   handlingSendEvent_ = handlingSendEvent;
 }
 
 - (IBAction)newDocument:(id)sender {
   content::ShellBrowserContext* browserContext =
       content::ShellContentBrowserClient::Get()->browser_context();
   content::Shell::CreateNewWindow(browserContext,
-                                  GURL("about:blank"),
+                                  GURL(content::kAboutBlankURL),
                                   NULL,
                                   MSG_ROUTING_NONE,
                                   gfx::Size());
 }
 
 @end