Retrieving the BluetoothManager system service requires an application context.

The MockContext we use for testing is not an application context (namely, it lacks
application info because it's meant to mock a service package, not an application).

In order to have a valid application context, we setup a test app and store its context
in a globally accessible location. Because the application context has global lifetime,
this is a reasonable thing to do.

Test: runtest
Change-Id: I5107707e63850a4861cc7e0788ce4a1de4753f19
3 files changed