Suppress new TSAN warnings from DMQuiltTask.

We're racing to invalidate the genID of our pixel ref when multiple
threads write into it, and also to call its genID-changed listeners.

We install no listeners on this particular pixel ref, nor do we ever
care about its genID at all.  So these are benign races, races on
data we never make a decision from.

BUG=skia:2725
R=jcgregorio@google.com, mtklein@google.com

Author: mtklein@chromium.org

Review URL: https://codereview.chromium.org/370353004
1 file changed