Add code to measure timer resolution on POSIX systems

Change-Id: I980f7e416725effe1872f2c5e75805d753e3b0ae
Reviewed-on: https://chromium-review.googlesource.com/1086994
Commit-Queue: Ivica Bogosavljevic <ivica.bogosavljevic@mips.com>
Reviewed-by: Michael Lippautz <mlippautz@chromium.org>
Cr-Commit-Position: refs/heads/master@{#53552}