Adds support for frame rate control in FrameGeneratorCapturer.

Bug: webrtc:9510
Change-Id: Idb062978a856ead994fce7e72402effcd8c719cf
Reviewed-on: https://webrtc-review.googlesource.com/95148
Reviewed-by: Erik Språng <sprang@webrtc.org>
Commit-Queue: Sebastian Jansson <srte@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#24499}
diff --git a/test/frame_generator_capturer.h b/test/frame_generator_capturer.h
index ac32fa4..6b2ed69 100644
--- a/test/frame_generator_capturer.h
+++ b/test/frame_generator_capturer.h
@@ -64,6 +64,7 @@
   void Start() override;
   void Stop() override;
   void ChangeResolution(size_t width, size_t height);
+  void ChangeFramerate(int target_framerate);
 
   void SetSinkWantsObserver(SinkWantsObserver* observer);
 
@@ -96,7 +97,8 @@
   rtc::CriticalSection lock_;
   std::unique_ptr<FrameGenerator> frame_generator_;
 
-  int target_fps_ RTC_GUARDED_BY(&lock_);
+  int source_fps_ RTC_GUARDED_BY(&lock_);
+  int target_capture_fps_ RTC_GUARDED_BY(&lock_);
   absl::optional<int> wanted_fps_ RTC_GUARDED_BY(&lock_);
   VideoRotation fake_rotation_ = kVideoRotation_0;