Allow other users to modify button settings

Change-Id: Id3b16f3fa3f1e7a8eaef42cfdc12e93dff3fed9b

Conflicts:
	res/xml/settings_headers.xml
Bluetooth: Set isPreferred to true for PanProfile Connections.

isPreferred is always true for PAN profile so that DUT can
initiate connection with remote device. Curretnly we are
returning true only when pan profile is in connected, so
it will return false when pan profile is not connected and
will never initiate connection on click.

Change-Id: I7c789add73ca944d074b0ecd8af223f6d61b547a
CRs-fixed: 463887
Bluetooth: Not allow Blank BT device name.

Add empty string check for BT device name
and not enable ok button until entered
device name is not empty.

Change-Id: Ib7c460bee5c8d86d13acd66d228279dd1a240c25
CRs-fixed: 471158
Bluetooth: Handle pairing Cancel intent.

Receive Pairing cancel intent and clear pairing request
from notification window.

CRs-fixed: 463362

Change-Id: I63c9299edca4356485f26cbc6332e3be9bdfbf17
Bluetooth: Handle BT search while rotate screen

Enable screen orientation in Settings app manifest.

CRs-Fixed: 519022
Change-Id: I74b70dafa1d8d12bf6770cb44a808cdf51555940