Add a test to verify switch Activity does not show the previous suggestion.

1. Fix onStartInputView does not clear the suggestion. If IME
don’t clear the suggestion, when the current Activity is not
autofillable, we will see suggestion of previous autofillable
Activity.

2. Add a new Activity which does not support autofill. Start an
autofillable Activity then trigger autofill. Switch to non-support
Activity, we should not see the suggestion in this Activity.

Bug: 157266998
Test: atest android.autofillservice.cts.inline#\
testAutofill_SwitchToNonAutofillableActivity

Change-Id: I85ba88d755d60cc0b78db18bedbf24c8e61cb12e
5 files changed