This is required to parse DIR_METADATA files.

Bug: 1135347
Change-Id: I620656d4dbec5e918bfc0f535397869c869446b8
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/tools/depot_tools/+/2644827
Commit-Queue: Henrique Nakashima <hnakashima@chromium.org>
Reviewed-by: Andrii Shyshkalov <tandrii@google.com>