Web Speech API: Fix a race condition causing renderer crash.

content/browser/speech/speech_recognition_manager_impl.h

 // 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.
 
 #ifndef CONTENT_BROWSER_SPEECH_SPEECH_RECOGNITION_MANAGER_IMPL_H_
 #define CONTENT_BROWSER_SPEECH_SPEECH_RECOGNITION_MANAGER_IMPL_H_
 
 #include <map>
 #include <string>
 
@@ skipping 109 matching lines @@
     EVENT_AUDIO_ENDED,
     EVENT_RECOGNITION_ENDED,
     EVENT_MAX_VALUE = EVENT_RECOGNITION_ENDED
   };
 
   struct Session {
     Session();
     ~Session();
 
     int id;
+    bool abort_requested;
     bool listener_is_active;
     SpeechRecognitionSessionConfig config;
     SpeechRecognitionSessionContext context;
     scoped_refptr<SpeechRecognizer> recognizer;
     scoped_ptr<MediaStreamUIProxy> ui;
   };
 
   // Callback issued by the SpeechRecognitionManagerDelegate for reporting
   // asynchronously the result of the CheckRecognitionIsAllowed call.
   void RecognitionAllowedCallback(int session_id,
@@ skipping 44 matching lines @@
 
   // Used for posting asynchronous tasks (on the IO thread) without worrying
   // about this class being destroyed in the meanwhile (due to browser shutdown)
   // since tasks pending on a destroyed WeakPtr are automatically discarded.
   base::WeakPtrFactory<SpeechRecognitionManagerImpl> weak_factory_;
 };
 
 }  // namespace content
 
 #endif  // CONTENT_BROWSER_SPEECH_SPEECH_RECOGNITION_MANAGER_IMPL_H_