Tracker's item count view grows with window width

[humdinger]

This is beta4, 64bit.

The view showing the item count and entry-point for drill-down-navigation in the bottom left corner of Tracker windows isn't fixed-size anymore. It grows horizontally when resizing the window:

#17901 is related in so far as if it were still fixed-size, there would be no resizing artifacts possible.

[waddlesplash]

It probably doesn't need to get as wide as it does in this screenshot but there is still reason to let it grow, perhaps for typeahead filtering.

[humdinger]

Yeah, if the view would resize dynamically if the space is needed, that would be best.

[humdinger]

Actually a duplicate of #16726.