Add content type information to encoded images and corresponding rtp extension header

webrtc/test/frame_generator_capturer.h

Index: webrtc/test/frame_generator_capturer.h
diff --git a/webrtc/test/frame_generator_capturer.h b/webrtc/test/frame_generator_capturer.h
index 3b2355ff0d3ac1433bb2c40d983c62e2921d6fd1..eb455874e36d560e701527c8199fcc97a82a0e3b 100644
--- a/webrtc/test/frame_generator_capturer.h
+++ b/webrtc/test/frame_generator_capturer.h
@@ -14,6 +14,7 @@
 #include <string>
 
 #include "webrtc/api/video/video_frame.h"
+#include "webrtc/api/video/video_content_type.h"
 #include "webrtc/base/criticalsection.h"
 #include "webrtc/base/task_queue.h"
 #include "webrtc/test/video_capturer.h"
@@ -65,6 +66,8 @@ class FrameGeneratorCapturer : public VideoCapturer {
   void ForceFrame();
   void SetFakeRotation(VideoRotation rotation);
 
+  void SetFakeContentType(VideoContentType content_type);
+
   int64_t first_frame_capture_time() const { return first_frame_capture_time_; }
 
   FrameGeneratorCapturer(Clock* clock,
@@ -89,6 +92,8 @@ class FrameGeneratorCapturer : public VideoCapturer {
   int target_fps_;
   VideoRotation fake_rotation_ = kVideoRotation_0;
 
+  VideoContentType fake_video_content_type_ = VideoContentType::kDefault;
+
   int64_t first_frame_capture_time_;
   // Must be the last field, so it will be deconstructed first as tasks
   // in the TaskQueue access other fields of the instance of this class.