Split a query used for updating moves after a delete in two separate
queries that are easier to understand to us and to the query optimizer.

This resolves a segfault when using the delete wc_db operation with
a path moved back to its original location.

* subversion/libsvn_wc/copy.c
  (copy_or_move): Stop reporting moved back nodes as degraded to delete.

* subversion/libsvn_wc/wc-queries.sql
  (STMT_SELECT_MOVED_PAIR): Remove selection of moves into the target
    tree.
  (STMT_UPDATE_MOVED_TO): New query, updating all moved-to's in a tree.

* subversion/libsvn_wc/wc_db.c
  (delete_node): Split usage of STMT_SELECT_MOVED_PAIR and replace some
    usage with STMT_UPDATE_MOVED_TO.

* subversion/tests/libsvn_wc/op-depth-test.c
  (test_funcs): Remove XFail from move_back test.


git-svn-id: https://svn.apache.org/repos/asf/subversion/trunk@1451282 13f79535-47bb-0310-9956-ffa450edef68