Makes RenderFrameObserver/RenderViewObserver::OnDestruct pure virtual.

content/renderer/pepper/pepper_media_device_manager.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 "content/renderer/pepper/pepper_media_device_manager.h"
 
 #include "base/location.h"
 #include "base/logging.h"
 #include "base/single_thread_task_runner.h"
 #include "base/threading/thread_task_runner_handle.h"
@@ skipping 237 matching lines @@
 
 MediaStreamDispatcher* PepperMediaDeviceManager::GetMediaStreamDispatcher()
     const {
   DCHECK(render_frame());
   MediaStreamDispatcher* const dispatcher =
       static_cast<RenderFrameImpl*>(render_frame())->GetMediaStreamDispatcher();
   DCHECK(dispatcher);
   return dispatcher;
 }
 
+void PepperMediaDeviceManager::OnDestruct() {
+  delete this;
+}
+
 }  // namespace content