@NotNull
  public Map<Key<?>, Object> getChangeContext(@NotNull Change change) {
    if (myRequestContext == null) return Collections.emptyMap();
    Map<Key<?>, Object> map = myRequestContext.get(change);
    return map == null ? Collections.emptyMap() : map;
  }
@NotNull
  public Map<Key<?>, Object> getChangeContext(@NotNull Change change)