RtcVideoEncoder: use the current timestamp for encoded frames.

content/renderer/media/rtc_video_encoder.cc

Index: content/renderer/media/rtc_video_encoder.cc
diff --git a/content/renderer/media/rtc_video_encoder.cc b/content/renderer/media/rtc_video_encoder.cc
index 4ce16d53834017eb35d2ea0a9922398047144ef6..cb7752ba848c66bb1f0957f2e07e7267341824c0 100644
--- a/content/renderer/media/rtc_video_encoder.cc
+++ b/content/renderer/media/rtc_video_encoder.cc
@@ -453,10 +453,10 @@ void RTCVideoEncoder::Impl::BitstreamBufferReady(int32_t bitstream_buffer_id,
     size_t payload_size,
     bool key_frame,
     base::TimeDelta timestamp) {
-  DVLOG(3) << "Impl::BitstreamBufferReady(): "
-              "bitstream_buffer_id=" << bitstream_buffer_id
-           << ", payload_size=" << payload_size
-           << ", key_frame=" << key_frame;
+  DVLOG(3) << "Impl::BitstreamBufferReady(): bitstream_buffer_id="
+           << bitstream_buffer_id << ", payload_size=" << payload_size
+           << ", key_frame=" << key_frame
+           << ", timestamp ms=" << timestamp.InMilliseconds();
   DCHECK(thread_checker_.CalledOnValidThread());
 
   if (bitstream_buffer_id < 0 ||
@@ -473,11 +473,17 @@ void RTCVideoEncoder::Impl::BitstreamBufferReady(int32_t bitstream_buffer_id,
   }
   output_buffers_free_count_--;
 
+  // CrOS Nyan provides invalid timestamp. Use the current time for now.
+  // TODO(wuchengli): use the timestamp in BitstreamBufferReady after Nyan is
+  // fixed. http://crbug.com/620565.
+  const int64_t capture_time_us = rtc::TimeMicros();
+
   // Derive the capture time (in ms) and RTP timestamp (in 90KHz ticks).
-  // This is based on how input timestamps are calculated in
-  // webrtc/video/video_capture_input.cc.
-  const uint32_t rtp_timestamp =
-      static_cast<uint32_t>(timestamp.InMilliseconds()) * 90;
+  const int64_t capture_time_ms =
+      capture_time_us / base::Time::kMicrosecondsPerMillisecond;
+
+  const uint32_t rtp_timestamp = static_cast<uint32_t>(
+      capture_time_us * 90 / base::Time::kMicrosecondsPerMillisecond);
 
   webrtc::EncodedImage image(
       reinterpret_cast<uint8_t*>(output_buffer->memory()), payload_size,
@@ -485,7 +491,7 @@ void RTCVideoEncoder::Impl::BitstreamBufferReady(int32_t bitstream_buffer_id,
   image._encodedWidth = input_visible_size_.width();
   image._encodedHeight = input_visible_size_.height();
   image._timeStamp = rtp_timestamp;
-  image.capture_time_ms_ = timestamp.InMilliseconds();
+  image.capture_time_ms_ = capture_time_ms;
   image._frameType =
       (key_frame ? webrtc::kVideoFrameKey : webrtc::kVideoFrameDelta);
   image._completeFrame = true;