Add BLUETOOTH_PRIVILEGED permission as a requirement for all new Bluetooth...

Add BLUETOOTH_PRIVILEGED permission as a requirement for all new Bluetooth SystemApis and for hidden connect/disconnect APIs.

Hide some APIs that were previously marked as @UnsupportedAppUsage and re-add annotation as changing the permissions for these SystemApis would break the unsupported app contract that was previously there. Therefore, we're choosing to hide them until we have a good story on how to deal with them next release.

Bug: 148689314
Test: Manual
Change-Id: I33ee2c7ccd3827db3d23d6447cf82d9ffc36836a