Disable virtual/threaded/.../worklet-animation-local-time-null-1

Looks like this has been failing flakily on Windows and Mac for a while;
most recently, it's caused the Mac10.13 Tests (dbg) builder to fail:

https://ci.chromium.org/p/chromium/builders/ci/Mac10.13%20Tests%20%28dbg%29

Tbr: gtsteel@chromium.org
Bug: 1126649
Change-Id: Ib3313cdcee9351d1e2bb1b4553456b2bc6c6e5d0
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2401973


Commit-Queue: David Van Cleve <davidvc@chromium.org>
Reviewed-by: David Van Cleve <davidvc@chromium.org>
Cr-Commit-Position: refs/heads/master@{#805593}