So I have looked around and found out that android.R.styleable is no longer part of the SDK even though it is still documented here.
That wouldn\'t real
This appears to be a bug in the SDK. I have filed an issue on it, which you may wish to star so as to receive updates on it.
As a worksaround, you can use reflection to access the field:
Class clazz=Class.forName("android.R$styleable");
int i=clazz.getField("Theme_backgroundDimAmount").getInt(clazz);