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..51749a3efddf95aed29590eddc5598d474ba4f58 100644
--- a/content/browser/renderer_host/media/media_stream_manager.h
+++ b/content/browser/renderer_host/media/media_stream_manager.h
@@ -17,6 +17,9 @@
 // 5. MediaStreamManager will call the proper media device manager to open the
 //    device and let the MediaStreamRequester know it has been done.
 
+// If either user or test harness selects --use-fake-device-for-media-stream,
+// a fake video device or devices are used instead of real ones.
+
 // When enumeration and open are done in separate operations,
 // MediaStreamUIController is not involved as in steps.
 
@@ -161,11 +164,6 @@ 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();
-
   // 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).
   void UseFakeUI(scoped_ptr<FakeMediaStreamUIProxy> fake_ui);