executor: fix two data races in tests#11120

Merged

jackysp merged 3 commits intopingcap:release-3.0from SunRunAway:automated-cherry-pick-of-#11062-release-3.0

Jul 8, 2019

Commits on Jul 8, 2019

fix two races

jackysp
authored and
SunRunAway
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remove useless code

jackysp
authored and
SunRunAway
committed
set oom action back

jackysp
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SunRunAway
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