@Override public Set<Entry<K, V>> entrySet() {
    EntrySet result = entrySet;
    return result != null ? result : (entrySet = new EntrySet());
  }
Rotates the subtree so that its root's left child is the new root.
lottie/src/main/java/com/airbnb/lottie/parser/moshi/LinkedHashTreeMap.java