Video capture Android: enable unittests for Camera2 API

media/capture/video/android/video_capture_device_android.cc

Index: media/capture/video/android/video_capture_device_android.cc
diff --git a/media/capture/video/android/video_capture_device_android.cc b/media/capture/video/android/video_capture_device_android.cc
index 58cc5fe1628dad89a95775e3f0f23d5180f64865..107610b8e24c99efc203df5baed1bc852231c683 100644
--- a/media/capture/video/android/video_capture_device_android.cc
+++ b/media/capture/video/android/video_capture_device_android.cc
@@ -420,6 +420,10 @@ void VideoCaptureDeviceAndroid::OnPhotoTaken(
   photo_callbacks_.erase(reference_it);
 }
 
+void VideoCaptureDeviceAndroid::ConfigureForTesting() {
+  Java_VideoCapture_setTestMode(AttachCurrentThread(), j_capture_);
+}
+
 VideoPixelFormat VideoCaptureDeviceAndroid::GetColorspace() {
   JNIEnv* env = AttachCurrentThread();
   const int current_capture_colorspace =