Let WebRtcVideoChannel2::WebRtcVideoSendStream::InputFrame carry the input frame's timestamp to out…

talk/media/webrtc/webrtcvideoengine2.h

 /*
  * libjingle
  * Copyright 2014 Google Inc.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are met:
  *
  *  1. Redistributions of source code must retain the above copyright notice,
  *     this list of conditions and the following disclaimer.
  *  2. Redistributions in binary form must reproduce the above copyright notice,
@@ skipping 375 matching lines @@
     VideoSendStreamParameters parameters_ GUARDED_BY(lock_);
     VideoEncoderSettings encoder_settings_ GUARDED_BY(lock_);
     AllocatedEncoder allocated_encoder_ GUARDED_BY(lock_);
     Dimensions last_dimensions_ GUARDED_BY(lock_);
 
     VideoCapturer* capturer_ GUARDED_BY(lock_);
     bool sending_ GUARDED_BY(lock_);
     bool muted_ GUARDED_BY(lock_);
     VideoFormat format_ GUARDED_BY(lock_);
     int old_adapt_changes_ GUARDED_BY(lock_);
+
+    // To align the delta timestamp with rtc time

[pthatcher1, 2015/07/15 17:53:07]

I like the comment on the other value, and think this should have a similar one:

// The timestamp of the first frame received
// Used to generate the timestamps of subsequent frames

[qiangchen, 2015/07/15 19:35:22]

Done.

+    int64_t base_timestamp_ms_ GUARDED_BY(lock_);
+
+    // The timestamp of the last frame we received
+    // Used to generate timestamp for the black frame when capturer is removed
+    int64_t last_timestamp_ms_ GUARDED_BY(lock_);
   };
 
   // Wrapper for the receiver part, contains configs etc. that are needed to
   // reconstruct the underlying VideoReceiveStream. Also serves as a wrapper
   // between webrtc::VideoRenderer and cricket::VideoRenderer.
   class WebRtcVideoReceiveStream : public webrtc::VideoRenderer {
    public:
     WebRtcVideoReceiveStream(
         webrtc::Call* call,
         const StreamParams& sp,
@@ skipping 121 matching lines @@
   WebRtcVideoDecoderFactory* const external_decoder_factory_;
   std::vector<VideoCodecSettings> recv_codecs_;
   std::vector<webrtc::RtpExtension> recv_rtp_extensions_;
   webrtc::Call::Config::BitrateConfig bitrate_config_;
   VideoOptions options_;
 };
 
 }  // namespace cricket
 
 #endif  // TALK_MEDIA_WEBRTC_WEBRTCVIDEOENGINE2_H_