This adds retry if target is old default branch. This may happen only if
user didn't fetch remote for extended period of time and old default
branch no longer exists.

R=ehmaldonado@chromium.org

Change-Id: I81981049ee006f68a073718180b454c230d055e9
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/tools/depot_tools/+/2473757
Commit-Queue: Josip Sokcevic <sokcevic@google.com>
Reviewed-by: Edward Lesmes <ehmaldonado@chromium.org>