The "Press tab or down to search" action text only makes sense when the heuristic is selected, when any other result is selected it doesn't make sense so we should change it.
We don't have a finalized spec here, we may want to either show nothing, or show something like "Select to search".

We're going to fix this with new copy. Tab-to-search results will say Search <engine name> directly from the address bar. We can just cover this when working on the existing tab-to-search bugs.