This test validates that all of the BatteryManager attributes exist and
are set to correct values, with corresponding events fired,
when the charger is plugged in.
The device is unplugged from the charger before this test is run.
The battery must not be full or reach full capacity before the time the test is run.
Plug in the charger and wait for all the tests to complete.
The tests may take long time since the definition of how
often the chargingtimechange, dischargingtimechange, and levelchange
events are fired is left to the implementation.