This uploads roll-branch CLs before landing and fixes an
ambiguity bug when pushing tags.

NOTRY=true
TBR=hablich@chromium.org

Bug: chromium:738679
Change-Id: I51e03d714ec97ee2d9bca4ecaf753d66038891c1
Reviewed-on: https://chromium-review.googlesource.com/558415Reviewed-by: Michael Achenbach <machenbach@chromium.org>
Commit-Queue: Michael Achenbach <machenbach@chromium.org>
Cr-Commit-Position: refs/heads/master@{#46382}