This change is backwards compatible.

R=dpranke@google.com

Bug: 1098560
Change-Id: Ic9447041a68b8c379f65900af11c89b006e3f806
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/tools/depot_tools/+/2285156
Commit-Queue: Josip Sokcevic <sokcevic@google.com>
Reviewed-by: Dirk Pranke <dpranke@google.com>