Fixes the collapsed view with images and different densities

Previously the collapsed view could contain a message even before
the messaging imaging image and the display would look very distored.
This now makes sure that any groups with isolated messages always
are the last ones displayed.

Test: add group with image, adjust display settings to large
Change-Id: If9e69f72ce117687898dcaea591e61c6fb49ef46
Fixes: 78490082