Change default timestamp to 64 bits in all webrtc directories.

webrtc/video/receive_statistics_proxy.cc

Index: webrtc/video/receive_statistics_proxy.cc
diff --git a/webrtc/video/receive_statistics_proxy.cc b/webrtc/video/receive_statistics_proxy.cc
index ff419249d4f2fe2bcb65d63115b391d5d7e2cf14..2579837f65b7cfbef001482735618e4a5018d863 100644
--- a/webrtc/video/receive_statistics_proxy.cc
+++ b/webrtc/video/receive_statistics_proxy.cc
@@ -27,8 +27,8 @@ ReceiveStatisticsProxy::ReceiveStatisticsProxy(
       // 1000ms window, scale 1000 for ms to s.
       decode_fps_estimator_(1000, 1000),
       renders_fps_estimator_(1000, 1000),
-      render_fps_tracker_(100u, 10u),
-      render_pixel_tracker_(100u, 10u) {
+      render_fps_tracker_(100, 10u),
+      render_pixel_tracker_(100, 10u) {
   stats_.ssrc = config.rtp.remote_ssrc;
   for (auto it : config.rtp.rtx)
     rtx_stats_[it.second.ssrc] = StreamDataCounters();