Calculate video padding for vp9 in the same way as for vp8

Bug: webrtc:11476
Change-Id: I8d7b5aac91868e10061605cc5043226ee916cc09
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/172722
Reviewed-by: Evan Shrubsole <eshr@google.com>
Reviewed-by: Niels Moller <nisse@webrtc.org>
Commit-Queue: Ilya Nikolaevskiy <ilnik@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#30982}
diff --git a/api/video/video_stream_encoder_interface.h b/api/video/video_stream_encoder_interface.h
index 253fb04..8e1df0f 100644
--- a/api/video/video_stream_encoder_interface.h
+++ b/api/video/video_stream_encoder_interface.h
@@ -44,6 +44,7 @@
    public:
     virtual void OnEncoderConfigurationChanged(
         std::vector<VideoStream> streams,
+        bool is_svc,
         VideoEncoderConfig::ContentType content_type,
         int min_transmit_bitrate_bps) = 0;
   };