MacViews: Gets a webview working in views_examples_with_content_exe

ui/views/controls/webview/webview.cc

 // 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 "ui/views/controls/webview/webview.h"
 
 #include "content/public/browser/browser_accessibility_state.h"
 #include "content/public/browser/browser_context.h"
 #include "content/public/browser/navigation_controller.h"
 #include "content/public/browser/render_view_host.h"
@@ skipping 347 matching lines @@
       content::BrowserContext* browser_context) {
   content::WebContents* contents = NULL;
   if (ViewsDelegate::views_delegate) {
     contents = ViewsDelegate::views_delegate->CreateWebContents(
         browser_context, NULL);
   }
 
   if (!contents) {
     content::WebContents::CreateParams create_params(
         browser_context, NULL);
+    create_params.context = GetWidget()->GetNativeView();
     return content::WebContents::Create(create_params);
   }
 
   return contents;
 }
 
 }  // namespace views