We have to handle the mediagroups size

Playlist and DVD menu buttons will hide with action bar, no need to set
them invisible

Remove savedIndexPosition variable which led to wrong index position

Use Build.SUPPORTED_ABIS after lollipop

Otherwise, old Android versions fail to register them.

Since it's used only from JNI.

Because we don't use the official way to build the jni lib.

IAWindowNativeHandler is now an abstract class

This reverts commit f6436a94.