expression: fix decimal of function FROM_UNIXTIME (#14936)#15270

Merged

sre-bot merged 4 commits intopingcap:release-3.0from sre-bot:release-3.0-7c39e5e5e0bc

Mar 12, 2020

+44-34

Commits on Mar 10, 2020

cherry pick pingcap#14936 to release-3.0

SunRunAway
authored and
sre-bot
committed
Update builtin_time.go
SunRunAway
authored

Commits on Mar 12, 2020