add option to shutdown after factory reset

Add a new hidden method to recovery system to trigger a factory reset
followed by a shutdown, rather than a reboot back to the regular
system.  Use this flag when the MASTER_CLEAR intent is broadcast with
a boolean extra "shutdown" set to true.

Change-Id: I2ceb25b715d9f0ef492a75b3d287d1e17cec89ef
2 files changed