Fix ECM issues

Fix crash in EmergencyCallbackModeExitDialog
* Return immediately if not in ECM and don't register receivers/show dialog
* Add more logging to diagnose future issues

Make sure ECM notification doesn't show up if emergency call is dialed twice
and then ECM mode dismissed.
* Fixed a timer leak that was causing the ECM notification to be posted
constantly even if we were out of ECM. This happens if ECMService has
startTimerNotification called and mTimer is not previously null.
* As a safeguard, if showNotification is called and we are already out of ECM,
stop the service.

Bug: 17958545
Change-Id: Ife3117eba2a750bc6a8e9cb59f3b5f55d563409a
2 files changed