Work around delayed killApplication() after APK installation

This CL aims to address the flakiness of
android.inputmethodservice.cts.hostside.MultiUserTest, which is
supposed to be caused by delayed killApplication() after APK
installations discussed in Bug 31009094.

What this CL does is adding a no-op test that does nothing bug waits 3
seconds.  That test should never fail, except for being killed by the
system, especially by the delayed killApplication() in question.

In this CL, we allow 3 retries before proceeding to the actual tests.

Fix: 132082599
Test: atest CtsInputMethodServiceHostTestCases:MultiUserTest
Change-Id: Ie1e425ca56aa7e856a52094b050b009fdef09309
3 files changed