Fix off-by-one bounds check on uniform location. Log an error when the user provides an invalid uniform location. Bug: chromium:1504162 Bug: chromium:1484878 Change-Id: Ieb7eb964d508954ac8dfa8e4d9bd941778185223 Reviewed-on: https://chromium-review.googlesource.com/c/angle/angle/+/5054238 Commit-Queue: Geoff Lang <geofflang@chromium.org> Reviewed-by: James Godfrey-Kittle <jamesgk@google.com>