Add CTS test for DialogWhenLarge and split screen.

This test exercises resizing a display containing an Activity with
the DialogWhenLarge theme from a dialog eligible size to a full
screen size. The test ensures the activity is still valid after the
transition.

Bug: 31643268
Test: cts/hostsidetests/services/activityandwindowmanager/util/run-test CtsServicesHostTestCases android.server.cts.ActivityManagerAppConfigurationTests#testDialogWhenLargeSplitSmall
Change-Id: I34f6fd7c49b91b7e4b1a9f023440661245e6010e
4 files changed