QUIC - added a histogram to measure the impact of reading QUIC server
information from disk cache on 0-RTT.

R=jar@chromium.org

Review URL: https://codereview.chromium.org/193253002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@256281 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 256281