Do not enforce PHONE_STATE_PERMISSION to register listener

PHONE_STATE_PERMISSION should not be required to register to the following
event types:
- PhoneStateListener.LISTEN_CALL_STATE
- PhoneStateListener.LISTEN_DATA_ACTIVITY
- PhoneStateListener.LISTEN_DATA_CONNECTION_STATE

In case of LISTEN_CALL_STATE, an empty string should be passed instead of
incomingNumber, when caller has no PHONE_STATE_PERMISSION.

Bug: 21588537
Change-Id: I5b6d0308924f7e4cd13a983b8e0c9b3a5bbb119b