text: /**
   * @license
   * Copyright 2016 Google Inc.
   *
   * Licensed under the Apache License, Version 2.0 (the "License");
   * you may not use this file except in compliance with the License.
   * You may obtain a copy of the License at
   *
   *     http://www.apache.org/licenses/LICENSE-2.0
   *
   * Unless required by applicable law or agreed to in writing, software
   * distributed under the License is distributed on an "AS IS" BASIS,
   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   * See the License for the specific language governing permissions and
   * limitations under the License.
   */
  
  
  goog.provide('shakaDemo.CloseButton');
  
  
  /**
   * A custom UI button, to allow users to close the video element.
   * This cannot actually extend shaka.ui.Element, as that class does not exist
   * at load-time when in uncompiled mode.
   * @extends {shaka.ui.Element}
   */
  shakaDemo.CloseButton = class extends shaka.ui.Element {
    /**
     * @param {!HTMLElement} parent
     * @param {!shaka.ui.Controls} controls
     */
    constructor(parent, controls) {
      super(parent, controls);
      this.button_ = document.createElement('button');
      this.button_.classList.add('material-icons-round');
      this.button_.classList.add('close-button');
      this.button_.textContent = 'close'; // Close icon.
      this.parent.appendChild(this.button_);
  
      this.button_.addEventListener('click', () => {
        shakaDemoMain.unload();
      });
  
      // TODO: Make sure that the screenreader description of this control is
      // localized!
    }
  
    /** @override */
    destroy() {
      return Promise.resolve();
    }
  };
  
  /**
   * @implements {shaka.extern.IUIElement.Factory}
   * @final
   */
  shakaDemo.CloseButton.Factory = class {
    /** @override */
    create(rootElement, controls) {
      return new shakaDemo.CloseButton(rootElement, controls);
    }
  };
  
  // This button is registered inside setup in shakaDemo.Main, rather than
  // statically here, since shaka.ui.Controls does not exist in this stage of the
  // load process.
  