Fix crash when pipeline is stopped while video restart is pending

media/renderers/renderer_impl.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 MEDIA_RENDERERS_RENDERER_IMPL_H_
 #define MEDIA_RENDERERS_RENDERER_IMPL_H_
 
 #include <memory>
 #include <vector>
 
@@ skipping 65 matching lines @@
 
  private:
   class RendererClientInternal;
 
   enum State {
     STATE_UNINITIALIZED,
     STATE_INIT_PENDING_CDM,  // Initialization is waiting for the CDM to be set.
     STATE_INITIALIZING,      // Initializing audio/video renderers.
     STATE_FLUSHING,
     STATE_PLAYING,
+    STATE_SHUTDOWN,
     STATE_ERROR
   };
 
   bool GetWallClockTimes(const std::vector<base::TimeDelta>& media_timestamps,
                          std::vector<base::TimeTicks>* wall_clock_times);
 
   bool HasEncryptedStream();
 
   void FinishInitialization(PipelineStatus status);
 
@@ skipping 104 matching lines @@
 
   base::WeakPtr<RendererImpl> weak_this_;
   base::WeakPtrFactory<RendererImpl> weak_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(RendererImpl);
 };
 
 }  // namespace media
 
 #endif  // MEDIA_RENDERERS_RENDERER_IMPL_H_