Refine BluetoothLeAdvertiser permissions.

Technically these APIs required both ADVERTISE and CONNECT, since
internally it would attempt getting the device name as part of
calculating packet lengths.  These methods shouldn't require the
CONNECT permission, so we add a getNameLengthForAdvertise() method
internally to remove this dependency.

Bug: 183626724
Test: ./build/soong/soong_ui.bash --make-mode Bluetooth RUN_ERROR_PRONE=true
Change-Id: Ic6c9528034ee7d4bdab6253394724294471b49f1