The Frequent apps grid has a few problems:
* On a fresh install there would be no history of app usage so the
applications shown in the grid have no relevance it takes time
to be useful instead of being useful from the start;
* The grid has far too many items in it to be relevant; 24 apps is
well beyond the average use case as most people don't frequently
use that many, so it gets populated with several apps that are
single use (hello xterm);
* The position of items in the grid are always changing based on an
unknown frequency metric (and not by user-intended input) which
makes it a poor way to quickly launch apps as one would have to
constantly learn the positions of the items in the grid;
* Having two app grids is a bit superfluous and needlessly complicates
the app launching navigation: you have to spend time checking the
frequent grid and if it's not there you have to switch over to another
grid and find the app you need in there it's not straightforward.
Remove the Frequent tab and simplify the related code.
Related: https://gitlab.gnome.org/GNOME/gnome-shell/issues/1425https://gitlab.gnome.org/GNOME/gnome-shell/merge_requests/880
548e19a7cd