Fix auto test failure of xmlpatterns on Mac

Autotest `tst_xmlpatterns.app/Contents/MacOS/tst_xmlpatterns' failed
  for macx-g++ cocoa OSX 10.7 x64 :(
  
    ********* Start testing of tst_XmlPatterns *********
    Config: Using QTest library 5.0.0, Qt 5.0.0
    PASS   : tst_XmlPatterns::initTestCase()
    FAIL!  : tst_XmlPatterns::xquerySupport(Load query via HTTP) Compared values are not the same
       Actual (fixedStderr): select: Invalid argument
    select: Invalid argument