[gold] Add support for chrome service accounts
[gold] Add support for chrome service accounts

Change-Id: I2d9954259e5f9813347662d23b167d779479bbc1
Bug: skia:12942
Reviewed-on: https://skia-review.googlesource.com/c/buildbot/+/508816
Reviewed-by: Leandro Lovisolo <f558143c2568be8d55575d13f30a1fc5cb8009d5@google.com>

google/skia-buildbot,google/skia-buildbot,google/skia-buildbot,google/skia-buildbot,google/skia-buildbot,google/skia-buildbot,google/skia-buildbot,google/skia-buildbot