VideoCapturerAndroid: Add possibility to request a new resolution from the video adapter.

BUG=
R=glaznev@webrtc.org

Review URL: https://codereview.webrtc.org/1178643006.

Cr-Commit-Position: refs/heads/master@{#9434}
diff --git a/talk/app/webrtc/androidvideocapturer.h b/talk/app/webrtc/androidvideocapturer.h
index 2dffb9c..2cfbdd8 100644
--- a/talk/app/webrtc/androidvideocapturer.h
+++ b/talk/app/webrtc/androidvideocapturer.h
@@ -74,6 +74,9 @@
                        int rotation,
                        int64 time_stamp);
 
+  // Called from JNI to request a new video format.
+  void OnOutputFormatRequest(int width, int height, int fps);
+
   AndroidVideoCapturerDelegate* delegate() { return delegate_.get(); }
 
  private: