Setting tooltip gravity to 's' so that the tooltip shows above

Right now the tooltip gravity is defaulting to north which causes
the tooltip to be partially overlapped by the cursor. Setting it
to south makes it easier to read since it appears above the icon
and isn't obscured by the cursor.

Change-Id: I9aa43c9ff93fbded1b51bf34c084ec0f8cad28b7
Merge "Setting tooltip gravity to 's' so that the tooltip shows above"