Re-land with protection against div-by-zero in samples compatibility
check.

BUG=722684

Change-Id: I3d5c310d1f2cb4d8b92d80492435855c3c4ad807
Reviewed-on: https://chromium-review.googlesource.com/517427Reviewed-by: Jamie Madill <jmadill@chromium.org>
Commit-Queue: Geoff Lang <geofflang@chromium.org>