Fix missing validation cache update on VAO binding. Bug: chromium:1139398 Change-Id: I85a0d7a72bc2c97b07ebc5f86effd8e36aefd544 Reviewed-on: https://chromium-review.googlesource.com/c/angle/angle/+/2485581 Reviewed-by: Geoff Lang <geofflang@chromium.org> Commit-Queue: Jamie Madill <jmadill@chromium.org>