The behavior of QTEST_MAIN depends on whether QT_GUI_LIB or QT_WIDGETS_LIB
is defined. It could create a QGuiApplication or QApplication which
could cause linking issues if the corresponding library is not linked to.
The failure cases are also tested.
Change-Id: I61ed0bc760564ef42ce1dbd86c83c06348c860ff
Reviewed-by: Rohan McGovern <rohan.mcgovern@nokia.com>