planner: fix plan cache statistic result. (#18067)#18111

Merged

ngaut merged 2 commits intopingcap:release-4.0from ti-srebot:release-4.0-7c4904903d1e

Jun 19, 2020

+39

Commits on Jun 18, 2020

cherry pick pingcap#18067 to release-4.0

danmay319
authored and
ti-srebot
committed

Commits on Jun 19, 2020

Merge branch 'release-4.0' into release-4.0-7c4904903d1e
ti-srebot
authored