Delete MediaStreamManager in the same way as AudioManager

content/browser/renderer_host/media/media_stream_manager.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.
 
 // MediaStreamManager is used to open/enumerate media capture devices (video
 // supported now). Call flow:
 // 1. GenerateStream is called when a render process wants to use a capture
 //    device.
 // 2. MediaStreamManager will ask MediaStreamDeviceSettings for permission to
 //    use devices and for which device to use.
@@ skipping 11 matching lines @@
 #ifndef CONTENT_BROWSER_RENDERER_HOST_MEDIA_MEDIA_STREAM_MANAGER_H_
 #define CONTENT_BROWSER_RENDERER_HOST_MEDIA_MEDIA_STREAM_MANAGER_H_
 
 #include <map>
 #include <string>
 #include <vector>
 
 #include "base/basictypes.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/memory/ref_counted.h"
+#include "base/message_loop.h"
 #include "base/threading/thread.h"
 #include "content/browser/renderer_host/media/media_stream_provider.h"
 #include "content/browser/renderer_host/media/media_stream_settings_requester.h"
 #include "content/common/media/media_stream_options.h"
 #include "content/common/content_export.h"
 #include "content/public/browser/browser_thread.h"
 
 namespace base {
 namespace win {
 class ScopedCOMInitializer;
@@ skipping 21 matching lines @@
   scoped_ptr<base::win::ScopedCOMInitializer> com_initializer_;
   DISALLOW_COPY_AND_ASSIGN(DeviceThread);
 };
 
 // MediaStreamManager is used to generate and close new media devices, not to
 // start the media flow.
 // The classes requesting new media streams are answered using
 // MediaStreamManager::Listener.
 class CONTENT_EXPORT MediaStreamManager
     : public MediaStreamProviderListener,
+      public MessageLoop::DestructionObserver,
       public SettingsRequester {
  public:
   // This class takes the ownerships of the |audio_input_device_manager|
   // and |video_capture_manager|.
   MediaStreamManager(AudioInputDeviceManager* audio_input_device_manager,
                      VideoCaptureManager* video_capture_manager);
 
   virtual ~MediaStreamManager();
 
   // Used to access VideoCaptureManager.
   VideoCaptureManager* video_capture_manager();
 
   // Used to access AudioInputDeviceManager.
   AudioInputDeviceManager* audio_input_device_manager();
 
-  // GenerateStream opens new media devices according to |components|. The
-  // request is identified using |label|, which is pointing to an already
-  // created std::string.
+  // GenerateStream opens new media devices according to |components|. It
+  // creates a new request which is identified by a unique |label| that's
+  // returned to the caller.
   void GenerateStream(MediaStreamRequester* requester, int render_process_id,
                       int render_view_id, const StreamOptions& options,
                       const GURL& security_origin, std::string* label);
 
   // Cancels all non-finished GenerateStream request, i.e. request for which
   // StreamGenerated hasn't been called.
   void CancelRequests(MediaStreamRequester* requester);
 
   // Cancel generate stream.
   void CancelGenerateStream(const std::string& label);
@@ skipping 37 matching lines @@
   virtual void DevicesAccepted(const std::string& label,
                                const StreamDeviceInfoArray& devices) OVERRIDE;
   virtual void SettingsError(const std::string& label) OVERRIDE;
 
   // Used by unit test to make sure fake devices are used instead of a real
   // devices, which is needed for server based testing.
   // TODO(xians): Remove this hack since we can create our own
   // MediaStreamManager in our unit tests.
   void UseFakeDevice();
 
+  // This object gets deleted on the UI thread after the IO thread has been
+  // destroyed. So we need to know when IO thread is being destroyed so that
+  // we can delete VideoCaptureManager and AudioInputDeviceManager.
+  virtual void WillDestroyCurrentMessageLoop() OVERRIDE;
+
  private:
   // Contains all data needed to keep track of requests.
   struct DeviceRequest;
 
   // Helpers for signaling the media observer that new capture devices are
   // opened/closed.
   void NotifyObserverDevicesOpened(DeviceRequest* request);
   void NotifyObserverDevicesClosed(DeviceRequest* request);
   void DevicesFromRequest(DeviceRequest* request,
                           content::MediaStreamDevices* devices);
@@ skipping 16 matching lines @@
   scoped_refptr<VideoCaptureManager> video_capture_manager_;
 
   // Keeps track of device types currently being enumerated to not enumerate
   // when not necessary.
   std::vector<bool> enumeration_in_progress_;
 
   // All non-closed request.
   typedef std::map<std::string, DeviceRequest> DeviceRequests;
   DeviceRequests requests_;
 
+  // Hold a pointer to the IO loop to check we delete the device thread and
+  // managers on the right thread.
+  MessageLoop* io_loop_;
+
   DISALLOW_COPY_AND_ASSIGN(MediaStreamManager);
 };
 
 }  // namespace media_stream
 
 #endif  // CONTENT_BROWSER_RENDERER_HOST_MEDIA_MEDIA_STREAM_MANAGER_H_