refactor

lib/android/app/src/main/java/com/reactnativenavigation/viewcontrollers/StackController.java

 	protected ViewGroup onCreateView() {
 		return new FrameLayout(getActivity());
 	}
-
-//	public ViewController getChildController(final int index) {
-//		Iterator<ViewController> it = childControllers.descendingIterator();
-//		int currentIndex = 0;
-//		while (it.hasNext()) {
-//			ViewController controller = it.next();
-//			if (currentIndex == index) {
-//				return controller;
-//			}
-//			currentIndex++;
-//		}
-//		return null;
-//	}
 }

lib/android/app/src/test/java/com/reactnativenavigation/viewcontrollers/StackControllerTest.java

 		assertHasSingleChildViewOfController(child2);
 	}
 
-//	@Test
-//	public void getControllerAtIndex() throws Exception {
-//		uut.push(child1);
-//		uut.push(child2);
-//		uut.push(child3);
-//		assertThat(uut.getChildController(0)).isEqualTo(child1);
-//		assertThat(uut.getChildController(1)).isEqualTo(child2);
-//		assertThat(uut.getChildController(2)).isEqualTo(child3);
-//		assertThat(uut.getChildController(3)).isNull();
-//	}
-
 	private void assertHasSingleChildViewOfController(ViewController childController) {
 		assertThat(uut.getView().getChildCount()).isEqualTo(1);
 		assertThat(uut.getView().getChildAt(0)).isEqualTo(childController.getView());