This will fix the issue where gclient didn't support checking
out DEPS-inside-DEPS. We pass a 'googletest_revision' variable
to third_party/googletest via recursedeps.

Bug: chromium:1017514
Change-Id: I4ef3785e385775910f24e13e60e284b8ab2996d6
Reviewed-on: https://chromium-review.googlesource.com/c/angle/angle/+/1881023Reviewed-by: Jamie Madill <jmadill@chromium.org>
Commit-Queue: Jamie Madill <jmadill@chromium.org>