Fix widget dependencies for multimediawidget tests and examples.

Change-Id: I9c7600ce2cf7980f923ba038ef122b49add24c37
Reviewed-on: http://codereview.qt-project.org/5286
Reviewed-by: Qt Sanity Bot <qt_sanity_bot@ovi.com>
Reviewed-by: Michael Goddard <michael.goddard@nokia.com>

tests/auto/qradiotuner/main.cpp

@@ -45,7 +45,7 @@
 
 int main(int argc, char**argv)
 {
-    QApplication app(argc,argv);
+    QCoreApplication app(argc,argv);
     int ret;
     tst_QRadioTuner test_api;
     ret = QTest::qExec(&test_api, argc, argv);