This will force "GN analyze" to pick up changes in the gold tests
when all that GN sees is a new SHA1 file. In effect a SHA1 change
means all the sources in a trace have changed.

Bug: chromium:1143507
Change-Id: Idf44045ebd5d2bda9380b339e95d336b6804ce8a
Reviewed-on: https://chromium-review.googlesource.com/c/angle/angle/+/2508530
Commit-Queue: Jamie Madill <jmadill@chromium.org>
Reviewed-by: Yuly Novikov <ynovikov@chromium.org>
Reviewed-by: Cody Northrop <cnorthrop@google.com>