Add a regression test for bug 228766370

..ensures that IME will visible an ime-focusable overlay window
when another activity behind the overlay that requests to show IME.

Fix: 232515113
Test: atest KeyboardVisiblityControlTest#\
        testImeVisibleOnImeFocusableOverlay
Change-Id: I1090a0a1b19d50742ebeeeeb2d3ba930c500e980
2 files changed