Change perf_test_runner to accept extra args. Bug: angleproject:5736 Change-Id: Ic6046c0b8c5ba9bc2f3bffda2c36eaceb24491ec Reviewed-on: https://chromium-review.googlesource.com/c/angle/angle/+/2855601 Reviewed-by: Tim Van Patten <timvp@google.com> Commit-Queue: Jamie Madill <jmadill@chromium.org>