Fix issue #1057.
Fix issue #1057.

* subversion/clients/cmdline/diff-cmd.c
  (svn_cl__diff): Punt if target1 is a URL but target2 is not.  (New
  issue #1061 is about adding the URL vs working file case.)


git-svn-id: f8a4e5e023278da1e04e203c7fe051e3c4285d88@844321 13f79535-47bb-0310-9956-ffa450edef68

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