Revert of Add a flags field to video timing extension.

webrtc/modules/video_coding/frame_object.cc

Index: webrtc/modules/video_coding/frame_object.cc
diff --git a/webrtc/modules/video_coding/frame_object.cc b/webrtc/modules/video_coding/frame_object.cc
index 86bcffb092be0bcb931c9b5fb667512636a2c2bb..1d858fcc0ea0febbd8917a262ed25187c05d19aa 100644
--- a/webrtc/modules/video_coding/frame_object.cc
+++ b/webrtc/modules/video_coding/frame_object.cc
@@ -32,7 +32,6 @@
     : packet_buffer_(packet_buffer),
       first_seq_num_(first_seq_num),
       last_seq_num_(last_seq_num),
-      timestamp_(0),
       received_time_(received_time),
       times_nacked_(times_nacked) {
   VCMPacket* first_packet = packet_buffer_->GetPacket(first_seq_num);
@@ -114,10 +113,10 @@
   rotation_ = last_packet->video_header.rotation;
   _rotation_set = true;
   content_type_ = last_packet->video_header.content_type;
-  if (last_packet->video_header.video_timing.flags !=
-      TimingFrameFlags::kInvalid) {
+  if (last_packet->video_header.video_timing.is_timing_frame) {
     // ntp_time_ms_ may be -1 if not estimated yet. This is not a problem,
     // as this will be dealt with at the time of reporting.
+    timing_.is_timing_frame = true;
     timing_.encode_start_ms =
         ntp_time_ms_ +
         last_packet->video_header.video_timing.encode_start_delta_ms;
@@ -139,8 +138,9 @@
 
     timing_.receive_start_ms = first_packet->receive_time_ms;
     timing_.receive_finish_ms = last_packet->receive_time_ms;
+  } else {
+    timing_.is_timing_frame = false;
   }
-  timing_.flags = last_packet->video_header.video_timing.flags;
 }
 
 RtpFrameObject::~RtpFrameObject() {