This is a reland of 67ef3f67

We no longer call cipd unconditionally.

Original change's description:
> gclient: delete unversioned directory before adding cipd dep for the same path
>
> Bug: 882611
> Change-Id: I46e41cc9693b90874b5d6569a12ec638eaac1050
> Reviewed-on: https://chromium-review.googlesource.com/1228655
> Commit-Queue: Edward Lesmes <ehmaldonado@chromium.org>
> Reviewed-by: Andrii Shyshkalov <tandrii@chromium.org>

Bug: 882611
Change-Id: I683bfc62bd1eebfec0853583f96f3981c2c6bdf2
Reviewed-on: https://chromium-review.googlesource.com/1232891Reviewed-by: Andrii Shyshkalov <tandrii@chromium.org>
Commit-Queue: Edward Lesmes <ehmaldonado@chromium.org>