Under Windows, display failing command lines in their quoted form.
Under Windows, display failing command lines in their quoted form.

The quoting can affect how the command is executed, so display the
quoted form to make it easier to debug the problem.

* subversion/tests/cmdline/svntest/main.py

  (open_pipe): Under Windows, return the *quoted* command line as part
  of the WAITER return value.


git-svn-id: f8a4e5e023278da1e04e203c7fe051e3c4285d88@878693 13f79535-47bb-0310-9956-ffa450edef68

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