Fix a potential error leak, and a potential uninitialized value.
Fix a potential error leak, and a potential uninitialized value.

* subversion/libsvn_wc/update_editor.c:
  (add_directory): only examine the switched case (for obstruction) if the
    wc_root case did not generate an error. move the err test inside the
    block, where we had assigned NULL to err before the checks. 


git-svn-id: f8a4e5e023278da1e04e203c7fe051e3c4285d88@928302 13f79535-47bb-0310-9956-ffa450edef68

wbond/subversion,wbond/subversion,wbond/subversion,wbond/subversion,YueLinHo/Subversion,wbond/subversion,wbond/subversion,YueLinHo/Subversion,YueLinHo/Subversion,YueLinHo/Subversion,wbond/subversion,YueLinHo/Subversion,YueLinHo/Subversion,YueLinHo/Subversion,YueLinHo/Subversion