Migrate WebRTC on FrameGeneratorInterface and remove FrameGenerator class

Bug: webrtc:10138
Change-Id: If85290581a72f81cf60181de7a7134cc9db7716e
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/161327
Reviewed-by: Niels Moller <nisse@webrtc.org>
Reviewed-by: Karl Wiberg <kwiberg@webrtc.org>
Commit-Queue: Artem Titov <titovartem@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#30033}
diff --git a/video/video_stream_encoder_unittest.cc b/video/video_stream_encoder_unittest.cc
index f2e023d..71d975a 100644
--- a/video/video_stream_encoder_unittest.cc
+++ b/video/video_stream_encoder_unittest.cc
@@ -39,7 +39,7 @@
 #include "test/encoder_settings.h"
 #include "test/fake_encoder.h"
 #include "test/field_trial.h"
-#include "test/frame_generator.h"
+#include "test/frame_forwarder.h"
 #include "test/gmock.h"
 #include "test/gtest.h"
 #include "test/video_encoder_proxy_factory.h"