Don't block setting the DEPTH_STENCIL attachment based on the resource format. By blocking the attachment at this point, it doesn't allow for the resource to have a depth stencil format later. BUG=997702 Change-Id: Iec5243012cb9a9527c5b1467d44c393b0dc6bddc Reviewed-on: https://chromium-review.googlesource.com/c/angle/angle/+/1780898 Commit-Queue: Geoff Lang <geofflang@chromium.org> Reviewed-by: Jonah Ryan-Davis <jonahr@google.com>