Fix gerrit_client py3 incompatibility
Fix gerrit_client py3 incompatibility

R=bdcbd10822f2f5deecea3bf14d73e9025b1b8375@google.com

Bug: 1255669
Change-Id: I4fbbe9fb716a6abd58f40c9ca489a0043ee3584b
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/tools/depot_tools/+/3214208
Reviewed-by: Gavin Mak <bdcbd10822f2f5deecea3bf14d73e9025b1b8375@google.com>
Commit-Queue: Josip Sokcevic <4606aec58cba917397ff2e4738f995e4758694f8@google.com>

CoherentLabs/depot_tools,CoherentLabs/depot_tools