Use repo_path_map in all places where patch_projects is currently used.
Add gclient.get_repo_path function to resolve path to a repo given its URL.

infra.git requires a non-trivial roll because of incorrect expectations.

Recipe-Nontrivial-Roll: build
Recipe-Nontrivial-Roll: infra
Bug: 877161
Change-Id: Iaea0a3f14609bf0c18d4ecdf8564153b8052584d
Reviewed-on: https://chromium-review.googlesource.com/1208363
Commit-Queue: Nodir Turakulov <nodir@chromium.org>
Reviewed-by: Andrii Shyshkalov <tandrii@chromium.org>