Some android builds are done when .git is not present.

BUG=angleproject:2344

Change-Id: Ic5418fb3b8161855e9c62d877eee22dabee846ef
Reviewed-on: https://chromium-review.googlesource.com/c/angle/angle/+/2090684Reviewed-by: Geoff Lang <geofflang@chromium.org>
Commit-Queue: Geoff Lang <geofflang@chromium.org>