Merge r1405922 from trunk:

 * r1405922
   Fix bug in error-constructing code in JavaHL.
   Justification:
     Bug that seems to be related to spurious JavaHL test failures I'm seeing,
     where absolute paths are passed into svn_relpath_dirname().
     Could cause worse issues such as abort() crashing Eclipse. Simple fix.
   Votes:
     +1: stsp, rhuijben


git-svn-id: https://svn.apache.org/repos/asf/subversion/branches/1.7.x@1491685 13f79535-47bb-0310-9956-ffa450edef68