Tested locally with chromium/src.
going from 17s -> <1s

Bug: 1339472
Change-Id: I71b90dcd6a7934ea7c9722dd040d63645792078e
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/tools/depot_tools/+/3791746
Commit-Queue: Joanna Wang <jojwang@chromium.org>
Reviewed-by: Gavin Mak <gavinmak@google.com>