With the old logic, a suppression shows up in the statistics independent if the test cases caused a difference or not. This doesn't give a signal if a suppression is useful. The new logic will help cleaning up suppressions that never apply.

BUG=chromium:673246
NOTRY=true
R=tandrii@chromium.org
TBR=mstarzinger@chromium.org,jarin@chromium.org

Change-Id: Iaebdac475f408f7d2649a34ccaa580c8d91e34a5
Reviewed-on: https://chromium-review.googlesource.com/437264Reviewed-by: Michael Achenbach <machenbach@chromium.org>
Reviewed-by: Andrii Shyshkalov <tandrii@chromium.org>
Commit-Queue: Michael Achenbach <machenbach@chromium.org>
Cr-Commit-Position: refs/heads/master@{#42932}