Code review comment for lp:~josharenson/unity8/dashboard-manager

Pretty good so far, just two minor things:
- why do the dividers have margins?
- we can get rid of the _source and "../" if we change the mocks to return a QVariant with qrc like we do in fake_previewwidgetmodel.cpp? we can add the dash icon to that same resource or create a new one (then fix where it needs to be adjusted)