How to use the @material/base/index.MDCComponent function in @material/base

* Copyright 2017 Google Inc. All Rights Reserved.
                                                      *
                                                      * 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
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class MDCToolbar extends _index.MDCComponent {
  static attachTo(root) {
    return new MDCToolbar(root);
  }

  get firstRowElement_() {
    return this.root_.querySelector(_foundation2.default.strings.FIRST_ROW_SELECTOR);
  }

  get titleElement_() {
    return this.root_.querySelector(_foundation2.default.strings.TITLE_SELECTOR);
  }

  set fixedAdjustElement(fixedAdjustElement) {
    this.fixedAdjustElement_ = fixedAdjustElement;
    this.foundation_.updateAdjustElementStyles();
  }