HOVER: Ensure to clear after reparenting all notifications

Change-Id: I1735a3983cbc5728c4bfe372d9cfd8a71551b4ac
HOVER: Fix notification content not being updated

Change-Id: I464be15de1bacafb8d29564a56f83b3e3780225c
HOVER: Match notification width on tablets too

Change-Id: I3f8cd27d09c9edba2934ee3838968ef9455122c5