Previously it was not possible to tell appart a linked data-block from its
override copy. In fact you couldn't tell appart any data-blocks with the same
name (which is possible with linking).
Now we show the library state icon as we do for data-blocks in other display
modes.
Old/new comparison (note the overriden "GEO-head"):
{F8608835} {F8608836}
8262e37d22