Was finding only "master" commits.

Change-Id: I434a0cb8d2112d6173e638814ad10f401c2fb9b3
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/tools/depot_tools/+/3226313Reviewed-by: Josip Sokcevic <sokcevic@google.com>
Reviewed-by: Dirk Pranke <dpranke@google.com>
Commit-Queue: Josip Sokcevic <sokcevic@google.com>
Auto-Submit: Andrew Grieve <agrieve@chromium.org>