Fix: Sort apps before opening AppDrawer to reflect the
most recent counts.

Repro:
 Clear Trebuchet data
 Drawer Sorting mode of Launch Count
 Launch App1 twice
 Launch App2 once
 Open drawer, note App1 ordered before App2
 Launcher App2 two more times
 Open drawer, note position hasn't updated

Change-Id: I9d85627f5dc86bc753a1e6f22911ee39a8d78b5e