Disable heap-snapshot-merged-nodes.js and heap-snapshot-with-event-listener.js on Mac

TBR=ulan@chromium.org, mlippautz@chromium.org, dgozman@chromium.org

Bug: 965356
Change-Id: Ia04d5bafa8329cde4ed99a0db90423a10623037d
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1621478
Reviewed-by: Fergus Dall <sidereal@google.com>
Cr-Commit-Position: refs/heads/master@{#661599}
1 file changed