Move pacer to fully use webrtc::Clock instead of webrtc::TickTime.

This required rewriting the send-side delay stats api to be callback based, as otherwise the SuspendBelowMinBitrate test started flaking much more frequently since it had lock order inversion problems.

R=pbos@webrtc.org, tommi@webrtc.org

Review URL: https://webrtc-codereview.appspot.com/21869005

git-svn-id: http://webrtc.googlecode.com/svn/trunk@6664 4adac7df-926f-26a2-2b94-8c16560cd09d
diff --git a/webrtc/config.h b/webrtc/config.h
index 9c8a902..2e96ec1 100644
--- a/webrtc/config.h
+++ b/webrtc/config.h
@@ -34,10 +34,17 @@
 };
 
 struct StreamStats {
-  StreamStats() : key_frames(0), delta_frames(0), bitrate_bps(0) {}
+  StreamStats()
+      : key_frames(0),
+        delta_frames(0),
+        bitrate_bps(0),
+        avg_delay_ms(0),
+        max_delay_ms(0) {}
   uint32_t key_frames;
   uint32_t delta_frames;
   int32_t bitrate_bps;
+  int avg_delay_ms;
+  int max_delay_ms;
   StreamDataCounters rtp_stats;
   RtcpStatistics rtcp_stats;
 };