How do you call closePanel in angular 5 autoComplete material

import {platformBrowserDynamic} from '@angular/platform-browser-dynamic';
import {BrowserModule} from '@angular/platform-browser';
import {BrowserAnimationsModule} from '@angular/platform-browser/animations';
import {NgModule} from '@angular/core';
import {FormsModule, ReactiveFormsModule} from '@angular/forms';
import {
  MatAutocompleteModule,
  MatButtonModule,
  MatButtonToggleModule,
  MatCardModule,
  MatCheckboxModule,
  MatChipsModule,
  MatCoreModule,
  MatDatepickerModule,
  MatDialogModule,
  MatExpansionModule,
  MatGridListModule,
  MatIconModule,
  MatInputModule,
  MatListModule,
  MatMenuModule,
  MatNativeDateModule,
  MatPaginatorModule,
  MatProgressBarModule,
  MatProgressSpinnerModule,
  MatRadioModule,
  MatRippleModule,
  MatSelectModule,
  MatSidenavModule,
  MatSliderModule,
  MatSlideToggleModule,
  MatSnackBarModule,
  MatSortModule,
  MatTableModule,
  MatTabsModule,
  MatToolbarModule,
  MatTooltipModule,
} from '@angular/material';
import {AutocompleteOverviewExample} from './autocomplete-overview-example';
import {HttpModule} from '@angular/http';

console.log(MatAutocompleteModule);
@NgModule({
  exports: [

    MatAutocompleteModule,
   
  ]
})
export class PlunkerMaterialModule {}

@NgModule({

  imports: [
    BrowserModule,
    BrowserAnimationsModule,
    FormsModule,
    HttpModule,
    PlunkerMaterialModule,

    ReactiveFormsModule,
  ],

  declarations: [AutocompleteOverviewExample],
  bootstrap: [AutocompleteOverviewExample],
  providers: []
})
export class PlunkerAppModule {}

platformBrowserDynamic().bootstrapModule(PlunkerAppModule);


/**  Copyright 2017 Google Inc. All Rights Reserved.
    Use of this source code is governed by an MIT-style license that
    can be found in the LICENSE file at http://angular.io/license */

import {Component, ViewChild} from '@angular/core';
import {FormControl} from '@angular/forms';
import { MatAutocompleteTrigger } from '@angular/material';
import 'rxjs/add/operator/startWith';
import 'rxjs/add/operator/map';

@Component({
  selector: 'autocomplete-overview-example',
  templateUrl: 'autocomplete-overview-example.html',
})
export class AutocompleteOverviewExample {
  stateCtrl: FormControl;
  filteredStates: any;
  
  @ViewChild('autoCompleteInput', { read: MatAutocompleteTrigger }) autoComplete: MatAutocompleteTrigger;

  close() {
    this.autoComplete.closePanel();
  }

  states = [
    'Alabama',
    'Alaska',
    'Arizona',
    'Arkansas',
    'California',
    'Colorado',
    'Connecticut',
    'Delaware',
    'Florida',
    'Georgia',
    'Hawaii',
    'Idaho',
    'Illinois',
    'Indiana',
    'Iowa',
    'Kansas',
    'Kentucky',
    'Louisiana',
    'Maine',
    'Maryland',
    'Massachusetts',
    'Michigan',
    'Minnesota',
    'Mississippi',
    'Missouri',
    'Montana',
    'Nebraska',
    'Nevada',
    'New Hampshire',
    'New Jersey',
    'New Mexico',
    'New York',
    'North Carolina',
    'North Dakota',
    'Ohio',
    'Oklahoma',
    'Oregon',
    'Pennsylvania',
    'Rhode Island',
    'South Carolina',
    'South Dakota',
    'Tennessee',
    'Texas',
    'Utah',
    'Vermont',
    'Virginia',
    'Washington',
    'West Virginia',
    'Wisconsin',
    'Wyoming',
  ];

  constructor() {
    this.stateCtrl = new FormControl();
    this.filteredStates = this.stateCtrl.valueChanges
        .startWith(null)
        .map(name => this.filterStates(name));
  }

  filterStates(val: string) {
    return val ? this.states.filter(s => s.toLowerCase().indexOf(val.toLowerCase()) === 0)
               : this.states;
  }

}


/**  Copyright 2017 Google Inc. All Rights Reserved.
    Use of this source code is governed by an MIT-style license that
    can be found in the LICENSE file at http://angular.io/license */

/** Add Transpiler for Typescript */
System.config({
  transpiler: 'typescript',
  typescriptOptions: {
    emitDecoratorMetadata: true
  },
  packages: {
    '.': {
      defaultExtension: 'ts'
    },
    'vendor': {
      defaultExtension: 'js'
    }
  }
});

System.config({
  map: {
    'main': 'main.js',

    // Angular specific mappings.
    '@angular/core': 'https://unpkg.com/@angular/core/bundles/core.umd.js',
    '@angular/animations': 'https://unpkg.com/@angular/animations/bundles/animations.umd.js',
    '@angular/common': 'https://unpkg.com/@angular/common/bundles/common.umd.js',
    '@angular/common/http': 'https://unpkg.com/@angular/common/bundles/common-http.umd.js',
    '@angular/compiler': 'https://unpkg.com/@angular/compiler/bundles/compiler.umd.js',
    '@angular/http': 'https://unpkg.com/@angular/http/bundles/http.umd.js',
    '@angular/forms': 'https://unpkg.com/@angular/forms/bundles/forms.umd.js',
    '@angular/router': 'https://unpkg.com/@angular/router/bundles/router.umd.js',
    '@angular/platform-browser': 'https://unpkg.com/@angular/platform-browser/bundles/platform-browser.umd.js',
    '@angular/platform-browser-dynamic': 'https://unpkg.com/@angular/platform-browser-dynamic/bundles/platform-browser-dynamic.umd.js',
    '@angular/animations/browser': 'https://unpkg.com/@angular/animations/bundles/animations-browser.umd.js',
    '@angular/platform-browser/animations': 'https://unpkg.com/@angular/platform-browser/bundles/platform-browser-animations.umd.js',
    '@angular/material': 'https://unpkg.com/@angular/material/bundles/material.umd.js',
    '@angular/cdk': 'https://unpkg.com/@angular/cdk/bundles/cdk.umd.js',
    '@angular/cdk/accordion': 'https://unpkg.com/@angular/cdk/bundles/cdk-accordion.umd.js',
    '@angular/cdk/a11y': 'https://unpkg.com/@angular/cdk/bundles/cdk-a11y.umd.js',
    '@angular/cdk/bidi': 'https://unpkg.com/@angular/cdk/bundles/cdk-bidi.umd.js',
    '@angular/cdk/coercion': 'https://unpkg.com/@angular/cdk/bundles/cdk-coercion.umd.js',
    '@angular/cdk/collections': 'https://unpkg.com/@angular/cdk/bundles/cdk-collections.umd.js',
    '@angular/cdk/layout': 'https://unpkg.com/@angular/cdk/bundles/cdk-layout.umd.js',
    '@angular/cdk/keycodes': 'https://unpkg.com/@angular/cdk/bundles/cdk-keycodes.umd.js',
    '@angular/cdk/observers': 'https://unpkg.com/@angular/cdk/bundles/cdk-observers.umd.js',
    '@angular/cdk/overlay': 'https://unpkg.com/@angular/cdk/bundles/cdk-overlay.umd.js',
    '@angular/cdk/platform': 'https://unpkg.com/@angular/cdk/bundles/cdk-platform.umd.js',
    '@angular/cdk/portal': 'https://unpkg.com/@angular/cdk/bundles/cdk-portal.umd.js',
    '@angular/cdk/rxjs': 'https://unpkg.com/@angular/cdk/bundles/cdk-rxjs.umd.js',
    '@angular/cdk/scrolling': 'https://unpkg.com/@angular/cdk/bundles/cdk-scrolling.umd.js',
    '@angular/cdk/table': 'https://unpkg.com/@angular/cdk/bundles/cdk-table.umd.js',
    '@angular/cdk/stepper': 'https://unpkg.com/@angular/cdk/bundles/cdk-stepper.umd.js',
    // Rxjs mapping
    'rxjs': 'https://unpkg.com/rxjs',
        'tslib': 'https://unpkg.com/tslib/tslib.js',
  },
  packages: {
    // Thirdparty barrels.
    'rxjs': { main: 'index' },
  }
});

<!DOCTYPE html>
<html>
<head>
  <title>Angular Material Plunker</title>

  <!-- Load common libraries -->
  <script src="https://cdnjs.cloudflare.com/ajax/libs/typescript/2.1.1/typescript.min.js"></script>
  <script src="https://cdnjs.cloudflare.com/ajax/libs/core-js/2.4.1/core.min.js"></script>
  <script src="https://cdnjs.cloudflare.com/ajax/libs/zone.js/0.8.5/zone.min.js"></script>
  <script src="https://cdnjs.cloudflare.com/ajax/libs/systemjs/0.19.38/system.js"></script>
  <script src="https://cdnjs.cloudflare.com/ajax/libs/hammer.js/2.0.8/hammer.min.js"></script>

  <!-- Configure SystemJS -->
  <script src="systemjs.config.js"></script>

  <script>
    System
      .import('main.ts')
      .catch(console.error.bind(console));
  </script>

  <!-- Load the Angular Material stylesheet -->
  <link href="https://unpkg.com/@angular/material/prebuilt-themes/indigo-pink.css" rel="stylesheet">
  <link href="https://fonts.googleapis.com/icon?family=Material+Icons" rel="stylesheet">
  <style>body { font-family: Roboto, Arial, sans-serif; }</style>
</head>

<body>
<autocomplete-overview-example>Loading Material Docs example...</autocomplete-overview-example>
</body>

</html>


<!-- Copyright 2017 Google Inc. All Rights Reserved.
    Use of this source code is governed by an MIT-style license that
    can be found in the LICENSE file at http://angular.io/license -->


  <input placeholder="State" #autoCompleteInput [matAutocomplete]="auto" [formControl]="stateCtrl">


<mat-autocomplete #auto="matAutocomplete">
  <mat-option *ngFor="let state of filteredStates | async" [value]="state">
    {{ state }}
  </mat-option>
</mat-autocomplete>

<button (click)="close()">Close</button>
 
<!-- Copyright 2017 Google Inc. All Rights Reserved.
    Use of this source code is governed by an MIT-style license that
    can be found in the LICENSE file at http://angular.io/license -->