Handle Emergency Callback Mode and Airplane Mode interactions

For UI interface consistency with airplane mode change from setting menu,
an ECM exit dialog should also be shown up when user wants to change airplane
mode in ECM after long key pressing power key. Then based on the user's choice to change
airplane mode. i.e. press Yes to exit ECM and turn on airplane mode or press No
to keep ECM and do not change airplane mode.

Change-Id: I0fe7e5cdeec0f33852615b491b75f65a46257590