Changes

Revert "Disable flaky test under TSan (see #14300) (#14301)"

This reverts commit 6aa7570edd5045e8e0f4d654133c529d8be71657.

Disabling the test is un-necessary now that the underlying issue has
been fixed by
  fb4dde52c7746e094769b929222af9e358a50e74
and
  14980901e121ea58bfac2574a8ac1ffc0ced0fc8.
 (commit: ab87321)