Issue caused by utf-8 vs byte mismatch in python 3.

Bug: 1009698
Change-Id: I8ab6b129ea9ab18f06f8ff4eb5da3aa018829365
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/tools/depot_tools/+/1832773
Commit-Queue: Edward Lesmes <ehmaldonado@chromium.org>
Reviewed-by: Anthony Polito <apolito@google.com>