Using git daemon for smoke tests times out on Windows.
This CL adds support for local directory URLs to gclient so we can tests
using local directories as remotes instead.

Bug: 1024683
Change-Id: I6dcefa6eb0a93713cf46ea1e4c6b29311ad37565
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/tools/depot_tools/+/1915416Reviewed-by: Anthony Polito <apolito@google.com>
Commit-Queue: Edward Lesmes <ehmaldonado@chromium.org>