This will be used in cases where git workspace is unavailable.
Bug: b/323243527
Change-Id: I51056cfbac50f76a0de1b98cfec488d8f133e353
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/tools/depot_tools/+/5263021
Commit-Queue: Gavin Mak <gavinmak@google.com>
Reviewed-by: Joanna Wang <jojwang@chromium.org>