This perf test highlights the performance hotspots with
State::syncProgramTextures.

Also includes a fix to the perf test runner script.

Bug: angleproject:2763
Change-Id: I69ffa0cc0d5e023944495b7a1c844770a54f7ddc
Reviewed-on: https://chromium-review.googlesource.com/1166041
Commit-Queue: Jamie Madill <jmadill@chromium.org>
Reviewed-by: Geoff Lang <geofflang@chromium.org>