Add Timestamp accessor methods to the EncodedImage class.

Bug: webrtc:9378
Change-Id: I59bf14f631f92f0f4e05f60d4af25641a23a53f9
Reviewed-on: https://webrtc-review.googlesource.com/82100
Reviewed-by: Stefan Holmer <stefan@webrtc.org>
Reviewed-by: Philip Eliasson <philipel@webrtc.org>
Reviewed-by: Rasmus Brandt <brandtr@webrtc.org>
Commit-Queue: Niels Moller <nisse@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#23734}
diff --git a/modules/video_coding/frame_object.cc b/modules/video_coding/frame_object.cc
index a3fc0d1..20e7565 100644
--- a/modules/video_coding/frame_object.cc
+++ b/modules/video_coding/frame_object.cc
@@ -26,7 +26,6 @@
     : 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);
@@ -69,7 +68,7 @@
   _encodedHeight = first_packet->height;
 
   // EncodedFrame members
-  timestamp = first_packet->timestamp;
+  SetTimestamp(first_packet->timestamp);
 
   VCMPacket* last_packet = packet_buffer_->GetPacket(last_seq_num);
   RTC_CHECK(last_packet);
@@ -140,10 +139,6 @@
   return packet_buffer_->GetBitstream(*this, destination);
 }
 
-uint32_t RtpFrameObject::Timestamp() const {
-  return timestamp_;
-}
-
 int64_t RtpFrameObject::ReceivedTime() const {
   return received_time_;
 }