* expression: fix Const.DeferredExpr's wrong behavior * clean the code * FIX UT * revert the change and add check for `funcCallToExpression` * solve conflicts * fix typo * address comments Co-authored-by: pingcap-github-bot <sre-bot@pingcap.com>
* expression: fix Const.DeferredExpr's wrong behavior * clean the code * FIX UT * revert the change and add check for `funcCallToExpression` * solve conflicts * fix typo * address comments Co-authored-by: pingcap-github-bot <sre-bot@pingcap.com>