test: fixed failure of tst_qgridlayout on small screens for non-QWS

This test will fail if the window manager doesn't give the widget the
geometry it requested.  The test was verifying this precondition, but
only on QWS.  It doesn't make sense to limit this check to QWS,
as  other platforms can have small screens too.

Change-Id: I3fec905c28ac2f85ebfd621f84f2269a673e318e
Reviewed-on: http://codereview.qt.nokia.com/3061
Reviewed-by: Qt Sanity Bot <qt_sanity_bot@ovi.com>
Reviewed-by: Kalle Lehtonen <kalle.ju.lehtonen@nokia.com>

tests/auto/qgridlayout/tst_qgridlayout.cpp

@@ -721,10 +721,8 @@ void tst_QGridLayout::spacingsAndMargins()
     QSize topsize = toplevel.size();
     QSize minimumsize = vbox.totalMinimumSize();
 
-#if defined(Q_WS_QWS)
     if (topsize.width() < minimumsize.width() || topsize.height() < minimumsize.height())
         QSKIP("The screen is too small to run this test case", SkipSingle);
-#endif
 
 // We are relying on the order here...
     for (int pi = 0; pi < sizehinters.count(); ++pi) {