ExpectAnim listener method add removal may be more appropriate?

[976112643]

ExpectAnim listener method add removal may be more appropriate?
ExpectAnim Listener 或许加上对应的移除方法更合适
Like this :

  public ExpectAnim removeEndListener(AnimationEndListener listener) {
        this.endListeners.remove(listener);
        return this;
    }

    public ExpectAnim removeStartListener(AnimationStartListener listener) {
        this.startListeners.remove(listener);
        return this;
    }