Stabilize resizemodeitem test.

Resizing can take time. Instead of qWait(50)
use QTRY_COMPARE to make sure we give enough time.

Change-Id: I484eca1f4d49381913dc82f405c73de653608493
Reviewed-by: Shawn Rutledge <shawn.rutledge@digia.com>
Reviewed-by: David Faure (KDE) <faure@kde.org>
Reviewed-by: Friedemann Kleint <Friedemann.Kleint@digia.com>

tests/auto/quick/qquickview/tst_qquickview.cpp

@@ -153,8 +153,7 @@ void tst_QQuickView::resizemodeitem()
 
     // size update from view
     view->resize(QSize(200,300));
-    QTest::qWait(50);
-    QCOMPARE(item->width(), 200.0);
+    QTRY_COMPARE(item->width(), 200.0);
     QCOMPARE(item->height(), 300.0);
     QCOMPARE(view->size(), QSize(200, 300));
     QCOMPARE(view->size(), view->sizeHint());