Starts a new request on switching back to the existing app

The response may be old and incorrect when leave the app then go back. To
avoid using the wrong response, going back to the app will trigger a new
request.

Bug: 146903532
Test: atest CtsAutoFillServiceTestCases
Change-Id: Ibab426183d39e3c51fb0f89ec6ba6ea48012b6a8
3 files changed