Making sure that SpeechRecognitionDispatcherHost is not used after free

content/browser/speech/speech_recognition_dispatcher_host.h

Index: content/browser/speech/speech_recognition_dispatcher_host.h
diff --git a/content/browser/speech/speech_recognition_dispatcher_host.h b/content/browser/speech/speech_recognition_dispatcher_host.h
index b50f260958d5156c00b690992de672d3c6ec18a9..e74447139a9e76e57ea7e982a6dc53ab86b729e3 100644
--- a/content/browser/speech/speech_recognition_dispatcher_host.h
+++ b/content/browser/speech/speech_recognition_dispatcher_host.h
@@ -6,6 +6,7 @@
 #define CONTENT_BROWSER_SPEECH_SPEECH_RECOGNITION_DISPATCHER_HOST_H_
 
 #include "base/memory/scoped_ptr.h"
+#include "base/memory/weak_ptr.h"
 #include "content/common/content_export.h"
 #include "content/public/browser/browser_message_filter.h"
 #include "content/public/browser/speech_recognition_event_listener.h"
@@ -31,6 +32,8 @@ class CONTENT_EXPORT SpeechRecognitionDispatcherHost
       int render_process_id,
       net::URLRequestContextGetter* context_getter);
 
+  base::WeakPtr<SpeechRecognitionDispatcherHost> AsWeakPtr();
+
   // SpeechRecognitionEventListener methods.
   virtual void OnRecognitionStart(int session_id) OVERRIDE;
   virtual void OnAudioStart(int session_id) OVERRIDE;
@@ -56,6 +59,8 @@ class CONTENT_EXPORT SpeechRecognitionDispatcherHost
       const IPC::Message& message,
       BrowserThread::ID* thread) OVERRIDE;
 
+  virtual void OnChannelClosing() OVERRIDE;
+
  private:
   virtual ~SpeechRecognitionDispatcherHost();
 
@@ -73,6 +78,11 @@ class CONTENT_EXPORT SpeechRecognitionDispatcherHost
   int render_process_id_;
   scoped_refptr<net::URLRequestContextGetter> context_getter_;
 
+  // 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<SpeechRecognitionDispatcherHost> weak_factory_;
+
   DISALLOW_COPY_AND_ASSIGN(SpeechRecognitionDispatcherHost);
 };