Add test for dynamic adding and removing layout items
Add test for dynamic adding and removing layout items

Change-Id: I7a92428e910435f0ecd63577cb12d5ce5b7653bc
Reviewed-by: Richard Moe Gustavsen <881e230b58d8abf8efbd9b8ce5a2db05f1d53614@digia.com>

drgvond/qtquickcontrols,kobolabs/qtquickcontrols,kobolabs/qtquickcontrols,mizukusak/qtquickcontrols,mizukusak/qtquickcontrols,mizukusak/qtquickcontrols,drgvond/qtquickcontrols,drgvond/qtquickcontrols,kobolabs/qtquickcontrols