Fixed several core and CTS tests

Fixes in framework include:
- ListPopupWindow requests focus for itself so it can receive
  MENU key.
- PopupWindow uses setTransitionVisibility to avoid losing
  focus upon enter transition.
- First-traversal will explicitly handle FOCUS_AFTER_DESCENDANTS
  on the current focus if applicable -- details in code comment.

Fixes in tests usually just required focusing what they expected
to have initial focus; however, there were a couple tests that
had been broken for other reasons for a long time.

app.cts.ActionBarTest
app.cts.ToolbarActionBarTest
android.view.DisabledLongpressTest
android.widget.scroll.arrowscroll.ShortButtonsTest
android.view.VisibilityTest
android.widget.listview.ListScrollListenerTest
android.widget.listview.arrowscroll.ListOfThinItemsTest
andorid.widget.listview.arrowscroll.ListWithNoFadingEdgeTest
android.view.LongpressTest
android.widget.focus.ScrollingThroughListOfFocusablesTest
android.widget.gridview.GridScrollListenerTest

Bug: 67467972
Test: Failing tests should pass now.
Change-Id: I9e2fbfeb183eb777f35c67eca53e1f70809b7670