Add back "non-robust" PLS queries Chrome doesn't have a codegen template for queries that model the "robust" signature, so support both types. Specify that the robust variants are only supported if ANGLE_robust_client_memory is supported, so Chrome and other implementations don't have to support them. Bug: chromium:1421437 Change-Id: Icc69b69ce9ce0a2cfad0dbeed1f3b29bcfa92d20 Reviewed-on: https://chromium-review.googlesource.com/c/angle/angle/+/4321867 Commit-Queue: Chris Dalton <chris@rive.app> Reviewed-by: Geoff Lang <geofflang@chromium.org>