code: private Node<T> moveRedRight(Node<T> h) {
          // assert (h != null);
          // assert isRed(h) && !isRed(h.right) && !isRed(h.right.left);
          flipColors(h);
          if (h.left.left != null && h.left.left.red) { 
              h = rotateRight(h);
              flipColors(h);
          }
          return h;
      }
docs: are black, make h.right or one of its children red.