Fix issue #2093608: Calendar widget takes a few seconds to launch

Avert your eyes!

The key change here is that RemoteViews can now call a Context API to
start its pending intent, which inside of the activity manager we can
use to determine to cancel the timeout delay for external entities
to disrupt the home screen.

Change-Id: If097cf7478cbed7a3c04a304050bd7fd5703d197