Require WebLocalFrame to be created with a non-null client

extensions/renderer/scoped_web_frame.h

 // Copyright 2015 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.
 
 #ifndef SCOPED_WEB_FRAME_H_
 #define SCOPED_WEB_FRAME_H_
 
 #include "base/macros.h"
+#include "third_party/WebKit/public/web/WebFrameClient.h"
 #include "third_party/WebKit/public/web/WebLocalFrame.h"
 #include "third_party/WebKit/public/web/WebView.h"
 
 namespace extensions {
 
 // ScopedWebFrame is a class to create a dummy webview and frame for testing.
 // The dymmy webview and frame will be destructed when the scope exits.
 class ScopedWebFrame {
 public:
   ScopedWebFrame();
   ~ScopedWebFrame();
 
   blink::WebLocalFrame* frame() { return frame_; }
 
 private:
-  // The webview and the frame are kept alive by the ScopedWebFrame
-  // because they are not destructed unless ~ScopedWebFrame explicitly
-  // closes the webview and the frame.
-  blink::WebView* view_;
-  blink::WebLocalFrame* frame_;
-  DISALLOW_COPY_AND_ASSIGN(ScopedWebFrame);
+ blink::WebFrameClient frame_client_;
+
+ // The webview and the frame are kept alive by the ScopedWebFrame
+ // because they are not destructed unless ~ScopedWebFrame explicitly
+ // closes the WebView.
+ blink::WebView* view_;
+ blink::WebLocalFrame* frame_;
+
+ DISALLOW_COPY_AND_ASSIGN(ScopedWebFrame);
 };
 
 }  // namespace extensions
 
 #endif  // SCOPED_WEB_FRAME_H_