Migrate androidx.test.uiautomator:integration-tests:testapp

Migrates integration tests with minimal changes needed for build/tests
to pass:
* Update package to androidx.test.uiautomator
* Replace android.support.test.* imports
* Mark UiObjectTests#testScrollDown and #testScrollDownToEnd as flaky
  (failed frequently in local testing)
* Ignore MultiWindowTests#testHasBackButton, #testHasHomeButton, and
  #testHasRecentsButton (makes assumptions about DUT)
* Full diff: gpaste/5676635689844736

Bug: 234650775
Test: ./gradlew :test:uiautomator:integration-tests:testapp:cAT
Relnote: N/A
No-Typo-Check: Will fix formatting/lint/typos separately.
Change-Id: Iebab0dd5b80669c4244d3d5d3107fcf3abe82975
diff --git a/settings.gradle b/settings.gradle
index b200c83..49e335c 100644
--- a/settings.gradle
+++ b/settings.gradle
@@ -786,6 +786,7 @@
 includeProject(":test:screenshot:screenshot")
 includeProject(":test:screenshot:screenshot-proto", "test/screenshot/screenshot/proto")
 includeProject(":test:uiautomator:uiautomator", [BuildType.MAIN])
+includeProject(":test:uiautomator:integration-tests:testapp", [BuildType.MAIN])
 includeProject(":text:text", [BuildType.COMPOSE])
 includeProject(":tracing:tracing")
 includeProject(":tracing:tracing-ktx")