Add facility for broadcasts receives to do work asynchronously.

You can now call goAsync() and move your work to a background thread.
If you are that kind of receiver.  You weirdo.

Also allows SharedPreferences.apply() to be committed off the main
thread after returning from onReceive().

Change-Id: I27f975910e28f230ababcaeb551eb9a78ec4fc76
5 files changed