Fix the Declarative WebRequest API for <webview>

chrome/browser/guest_view/guest_view.h

 // Copyright 2014 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 CHROME_BROWSER_GUEST_VIEW_GUEST_VIEW_H_
 #define CHROME_BROWSER_GUEST_VIEW_GUEST_VIEW_H_
 
 #include "chrome/browser/guest_view/guest_view_base.h"
 
+// A GuestView is the templated base class for out-of-process frames in the
+// chrome layer. GuestView is templated on its derived type to allow for type-
+// safe access. See GuestViewBase for more information.
 template <typename T>
 class GuestView : public GuestViewBase {
  public:
   static T* From(int embedder_process_id, int guest_instance_id) {
     GuestViewBase* guest =
         GuestViewBase::From(embedder_process_id, guest_instance_id);
     if (!guest)
       return NULL;
     return guest->As<T>();
   }
@@ skipping 25 matching lines @@
             const std::string& embedder_extension_id)
       : GuestViewBase(guest_instance_id,
                       guest_web_contents,
                       embedder_extension_id) {}
 
  private:
   DISALLOW_COPY_AND_ASSIGN(GuestView);
 };
 
 #endif  // CHROME_BROWSER_GUEST_VIEW_GUEST_VIEW_H_