Do not add default emergency account when there is no telephony and

use RegisterReceiverAsUser to receiver use switch related events
properly.

Test:  local test. adb shell setprop ril.ecclist 911,122,*911,#911,411.
And then manual test that the bluetooth phone account is chosen for
411 ecall and verify after phone is disconnected, call contacts
are cleared

Bug: 138684166

Change-Id: Ia9d86dc08bbc14cc0b82592473da915666c398fa