Missing RecyclerView ScrollListener API

RecyclerUtils.java

package whatever;

import android.support.v7.widget.RecyclerView;

import java.lang.reflect.Field;
import java.util.HashSet;

/**
 * Created by vishna on 28/10/14.
 */
public class RecyclerUtils {
   public static void addOnScrollListener(RecyclerView recyclerView, RecyclerView.OnScrollListener onScrollListener) {
      if (recyclerView == null || onScrollListener == null) {
         return;
      }
      WrappedOnScrollListener wrappedOnScrollListener = getOnScrollListener(recyclerView);
      if (wrappedOnScrollListener != null) {
         wrappedOnScrollListener.addListener(onScrollListener);
      }
   }

   public static void removeOnScrollListener(RecyclerView recyclerView, RecyclerView.OnScrollListener onScrollListener) {
      if (recyclerView == null || onScrollListener == null) {
         return;
      }
      WrappedOnScrollListener wrappedOnScrollListener = getOnScrollListener(recyclerView);
      if (wrappedOnScrollListener != null) {
         wrappedOnScrollListener.removeListener(onScrollListener);
      }
   }

   public static WrappedOnScrollListener getOnScrollListener(RecyclerView listView) {
      if (listView == null)
         return null;
      WrappedOnScrollListener result = null;
      // try to access private OnScrollListener mOnScrollListener; through reflection
      try {
         Field f = RecyclerView.class.getDeclaredField("mScrollListener");
         f.setAccessible(true);
         RecyclerView.OnScrollListener onScrollListener = (RecyclerView.OnScrollListener) f.get(listView);
         if (onScrollListener == null) {
            // no listener whatsoever
            result = new WrappedOnScrollListener();
            listView.setOnScrollListener(result);
         } else if (onScrollListener instanceof WrappedOnScrollListener) {
            result = (WrappedOnScrollListener) onScrollListener;
         } else {
            // a listener has been setup but it's not an instance of the WrappedOnScrollListener class
            // replace the existing listener with a wrapper, add existing one to the wrapper
            result = new WrappedOnScrollListener();
            result.addListener(onScrollListener);
            listView.setOnScrollListener(result);
         }
      } catch (NoSuchFieldException e) {} catch (IllegalAccessException e) {}
      return result;
   }

   public static class WrappedOnScrollListener extends RecyclerView.OnScrollListener {

      public void addListener(RecyclerView.OnScrollListener listener) {
         listeners.add(listener);
      }

      public void removeListener(RecyclerView.OnScrollListener listener) {
         listeners.remove(listener);
      }

      HashSet<RecyclerView.OnScrollListener> listeners = new HashSet<RecyclerView.OnScrollListener>();

      @Override public void onScrollStateChanged(RecyclerView recyclerView, int newState) {
         for (RecyclerView.OnScrollListener listener : listeners)
            listener.onScrollStateChanged(recyclerView, newState);
      }

      @Override
      public void onScrolled(RecyclerView recyclerView, int dx, int dy) {
         for (RecyclerView.OnScrollListener listener : listeners)
            listener.onScrolled(recyclerView, dx, dy);
      }
   }
}