Use a single query to determine which records need their moved_to updated
during delete. This should handle many issues currently not covered by tests
where moves are not stored in the highest op-depth.

* subversion/libsvn_wc/wc-queries.sql
  (STMT_SELECT_MOVED_PAIR): Delete query.
  (STMT_SELECT_MOVED_FOR_DELETE): New query.

* subversion/libsvn_wc/wc_db.c
  (delete_node): Don't perform unnecessary double allocation. Remove specific
    query for special directory case. Process all moved descendants in one
    place instead.


git-svn-id: https://svn.apache.org/repos/asf/subversion/trunk@1451413 13f79535-47bb-0310-9956-ffa450edef68