Extract VideoCaptureDeviceFactory out of VideoCaptureDevice and use for File and FakeVCD.

content/browser/renderer_host/media/media_stream_manager.h

Index: content/browser/renderer_host/media/media_stream_manager.h
diff --git a/content/browser/renderer_host/media/media_stream_manager.h b/content/browser/renderer_host/media/media_stream_manager.h
index 17bc6d231d1cd60e1aa56ca0d854975e42cf5eb8..27772ca90ba94d0459d94d76a98aeb8ab2bdd3f4 100644
--- a/content/browser/renderer_host/media/media_stream_manager.h
+++ b/content/browser/renderer_host/media/media_stream_manager.h
@@ -38,6 +38,7 @@
 #include "content/common/media/media_stream_options.h"
 #include "content/public/browser/media_request_state.h"
 #include "content/public/browser/resource_context.h"
+#include "media/video/capture/video_capture_device_factory.h"
 
 namespace media {
 class AudioManager;
@@ -161,10 +162,12 @@ class CONTENT_EXPORT MediaStreamManager
   virtual void OnDevicesChanged(
       base::SystemMonitor::DeviceType device_type) OVERRIDE;
 
-  // Used by unit test to make sure fake devices are used instead of a real
-  // devices, which is needed for server based testing or certain tests (which
-  // can pass --use-fake-device-for-media-stream).
-  void UseFakeDevice();
+  // Used by unit test to make sure that a fake video device or devices are used
+  // instead of real ones, which is needed for server based testing or certain
+  // tests (which can pass --use-fake-device-for-media-stream).
+  void UseFakeVideoDevice(scoped_ptr<media::VideoCaptureDeviceFactory> factory);
+  // Same as the previous for using a fake audio device or devices.
+  void UseFakeAudioDevice();
 
   // Called by the tests to specify a fake UI that should be used for next
   // generated stream (or when using --use-fake-ui-for-media-stream).