Method setupOverflow

packages/fairygui/src/core/GComponent.ts:688–693

* Setup overflow behavior * 设置溢出行为

(overflow: EOverflowType)

     * 设置溢出行为
     */
    protected setupOverflow(overflow: EOverflowType): void {
        this._overflow = overflow;
        if (overflow === EOverflowType.Hidden) {
            this._clipRect = new Rectangle(0, 0, this._width, this._height);
        }
    }

    // Construction from resource | 从资源构建