The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/dfbd0976c29da9edc48671ba785861abd007742e

commit dfbd0976c29da9edc48671ba785861abd007742e
Author: rch <rch@chromium.org>
Date: Sun Aug 14 13:34:08 2016

Add histograms to record QUIC Min and Smoothed RTT.

BUG= 637314 

Review-Url: https://codereview.chromium.org/2239103002
Cr-Commit-Position: refs/heads/master@{#411918}

[modify] https://crrev.com/dfbd0976c29da9edc48671ba785861abd007742e/net/quic/chromium/quic_connection_logger.cc
[modify] https://crrev.com/dfbd0976c29da9edc48671ba785861abd007742e/tools/metrics/histograms/histograms.xml