protected int compareTo0(OffsettedItem other) {
    throw new UnsupportedOperationException("unsupported");
  }
Compares this instance to another which is guaranteed to be of the same class. The default
implementation of this method is to throw an exception (unsupported operation). If a particular
class needs to actually sort, then it should override this method.

@param other {@code non-null;} instance to compare to
@return {@code -1}, {@code 0}, or {@code 1}, depending on the sort order of this instance and
    the other
android/android_framework/dex-maker/src/main/java/com/android/dx/dex/file/OffsettedItem.java