stub FocusFinder to fix crash when pressing arrow keys

Since we now have basic support for keyboard input, new code paths can
be reached. For example in the ViewPager in the MainActivity of NewPipe.

src/api-impl/android/view/SoundEffectConstants.java

@@ -0,0 +1,9 @@
+package android.view;
+
+public class SoundEffectConstants {
+
+	// the typo is part of the API
+	public static int getContantForFocusDirection(int direction) {
+		return 0;
+	}
+}