Revert of Request keyframes more frequently on stream start/decoding error.

webrtc/modules/video_coding/frame_object.h

Index: webrtc/modules/video_coding/frame_object.h
diff --git a/webrtc/modules/video_coding/frame_object.h b/webrtc/modules/video_coding/frame_object.h
index 5299ed8152a59827fadccfd3070178ec4c12ec10..07510770417ef6f09a12cc0293bb32c186bab269 100644
--- a/webrtc/modules/video_coding/frame_object.h
+++ b/webrtc/modules/video_coding/frame_object.h
@@ -43,8 +43,6 @@
   virtual bool delayed_by_retransmission() const { return 0; }
 
   size_t size() const { return _length; }
-
-  bool is_keyframe() const { return num_references == 0; }
 
   // The tuple (|picture_id|, |spatial_layer|) uniquely identifies a frame
   // object. For codec types that don't necessarily have picture ids they