This test runner can run the tests in an infinite loop, giving much
lower variance. It also automatically parses the output from several
runs and prints out the mean and standard deviation of the population.

BUG=None

Change-Id: Ic9f6f7d3158e93949a8e17c99ea1e3856eb34076
Reviewed-on: https://chromium-review.googlesource.com/312262Reviewed-by: Jamie Madill <jmadill@chromium.org>
Tested-by: Jamie Madill <jmadill@chromium.org>