Following up on r1501338, avoid using a separate db query for the wq items exists check.
Following up on r1501338, avoid using a separate db query for the wq items
exists check.

* subversion/libsvn_wc/wc_db.c
  (wclock_obtain_cb): Enforce empty workqueue in the existing transaction for
    this operation, here.
  (svn_wc__db_wclock_obtain): Instead of here.


git-svn-id: f8a4e5e023278da1e04e203c7fe051e3c4285d88@1501360 13f79535-47bb-0310-9956-ffa450edef68

YueLinHo/Subversion,YueLinHo/Subversion,YueLinHo/Subversion,YueLinHo/Subversion,YueLinHo/Subversion,YueLinHo/Subversion,YueLinHo/Subversion,YueLinHo/Subversion