Use factory method to create VideoCaptureDeviceFactory .

media/video/capture/android/video_capture_device_factory_android.cc

Index: media/video/capture/android/video_capture_device_factory_android.cc
diff --git a/media/video/capture/android/video_capture_device_factory_android.cc b/media/video/capture/android/video_capture_device_factory_android.cc
index 010c1949eb65338e83dd56249138f869aba5987f..dd9e2fc2f7b067921fb0a229180f41e78137f9be 100644
--- a/media/video/capture/android/video_capture_device_factory_android.cc
+++ b/media/video/capture/android/video_capture_device_factory_android.cc
@@ -123,4 +123,11 @@ void VideoCaptureDeviceFactoryAndroid::GetDeviceSupportedFormats(
   }
 }
 
+// static
+VideoCaptureDeviceFactory*
+VideoCaptureDeviceFactory::CreateVideoCaptureDeviceFactory(
+    scoped_refptr<base::SingleThreadTaskRunner> ui_task_runner) {
+  return new VideoCaptureDeviceFactoryAndroid();
+}
+
 }  // namespace media