Fix format/internalformat confusion Bug: angleproject:4084 Change-Id: I24a184b78bef2994a3045b141ecd72a49d66cfdf Reviewed-on: https://chromium-review.googlesource.com/c/angle/angle/+/1934890 Reviewed-by: Jamie Madill <jmadill@chromium.org> Reviewed-by: Geoff Lang <geofflang@chromium.org> Commit-Queue: James Darpinian <jdarpinian@chromium.org>