title: Getting error after adding web worker with cli command in Angular 8
body: <p>Angular 8 has added a better support for web workers. I had no luck to get it working. Does someone know what am i doing wrong?</p>
  
  <p><a href="https://angular.io/guide/web-worker" rel="nofollow noreferrer">Here is official guide</a> i followed.</p>
  
  <p>With this cli command i generated web worker:</p>
  
  <pre><code>ng generate webWorker my-worker
  </code></pre>
  
  <p>cli has generated my-worker.worker.ts file and tsconfig.worker.json file,  and updated following files: angular.json, tsconfig.app.json.</p>
  
  <p>After this im getting following error:</p>
  
  <pre><code>ERROR in node_modules/typescript/lib/lib.dom.d.ts(25,1): error TS6200: Definitions of the following identifiers conflict with those in another file: EventListenerOrEventListenerObject, BlobPart, HeadersInit, BodyInit, RequestInfo, DOMHighResTimeStamp, CanvasImageSource, MessageEventSource, ImageBitmapSource, TimerHandler, PerformanceEntryList, VibratePattern, AlgorithmIdentifier, HashAlgorithmIdentifier, BigInteger, NamedCurve, GLenum, GLboolean, GLbitfield, GLint, GLsizei, GLintptr, GLsizeiptr, GLuint, GLfloat, GLclampf, TexImageSource, Float32List, Int32List, BufferSource, DOMTimeStamp, FormDataEntryValue, IDBValidKey, Transferable, BinaryType, ClientTypes, EndingType, IDBCursorDirection, IDBRequestReadyState, IDBTransactionMode, KeyFormat, KeyType, KeyUsage, NotificationDirection, NotificationPermission, PushEncryptionKeyName, PushPermissionState, ReferrerPolicy, RequestCache, RequestCredentials, RequestDestination, RequestMode, RequestRedirect, ResponseType, ServiceWorkerState, ServiceWorkerUpdateViaCache, VisibilityState, WebGLPowerPreference, WorkerType, XMLHttpRequestResponseType
  node_modules/typescript/lib/lib.dom.d.ts(3473,5): error TS2687: All declarations of 'privateKey' must have identical modifiers.
  node_modules/typescript/lib/lib.dom.d.ts(3474,5): error TS2687: All declarations of 'publicKey' must have identical modifiers.
  node_modules/typescript/lib/lib.webworker.d.ts(25,1): error TS6200: Definitions of the following identifiers conflict with those in another file: EventListenerOrEventListenerObject, BlobPart, HeadersInit, BodyInit, RequestInfo, DOMHighResTimeStamp, CanvasImageSource, MessageEventSource, ImageBitmapSource, TimerHandler, PerformanceEntryList, VibratePattern, AlgorithmIdentifier, HashAlgorithmIdentifier, BigInteger, NamedCurve, GLenum, GLboolean, GLbitfield, GLint, GLsizei, GLintptr, GLsizeiptr, GLuint, GLfloat, GLclampf, TexImageSource, Float32List, Int32List, BufferSource, DOMTimeStamp, FormDataEntryValue, IDBValidKey, Transferable, BinaryType, ClientTypes, EndingType, IDBCursorDirection, IDBRequestReadyState, IDBTransactionMode, KeyFormat, KeyType, KeyUsage, NotificationDirection, NotificationPermission, PushEncryptionKeyName, PushPermissionState, ReferrerPolicy, RequestCache, RequestCredentials, RequestDestination, RequestMode, RequestRedirect, ResponseType, ServiceWorkerState, ServiceWorkerUpdateViaCache, VisibilityState, WebGLPowerPreference, WorkerType, XMLHttpRequestResponseType
  node_modules/typescript/lib/lib.webworker.d.ts(85,5): error TS2687: All declarations of 'privateKey' must have identical modifiers.
  node_modules/typescript/lib/lib.webworker.d.ts(86,5): error TS2687: All declarations of 'publicKey' must have identical modifiers.
  node_modules/typescript/lib/lib.webworker.d.ts(1074,5): error TS2375: Duplicate number index signature.
  node_modules/typescript/lib/lib.webworker.d.ts(1360,5): error TS2375: Duplicate number index signature.
  node_modules/typescript/lib/lib.webworker.d.ts(1434,13): error TS2403: Subsequent variable declarations must have the same type.  Variable 'FormData' must be of type '{ new (form?: HTMLFormElement): FormData; prototype: FormData; }', but here has type '{ new (): FormData; prototype: FormData; }'.
  node_modules/typescript/lib/lib.webworker.d.ts(2170,13): error TS2403: Subsequent variable declarations must have the same type.  Variable 'Notification' must be of type '{ new (title: string, options?: NotificationOptions): Notification; prototype: Notification; readonly maxActions: number; readonly permission: NotificationPermission; requestPermission(deprecatedCallback?: NotificationPermissionCallback): Promise&lt;...&gt;; }', but here has type '{ new (title: string, options?: NotificationOptions): Notification; prototype: Notification; readonly maxActions: number; readonly permission: NotificationPermission; }'.
  node_modules/typescript/lib/lib.webworker.d.ts(4322,13): error TS2403: Subsequent variable declarations must have the same type.  Variable 'onmessage' must be of type '(this: Window, ev: MessageEvent) =&gt; any', but here has type '(this: DedicatedWorkerGlobalScope, ev: MessageEvent) =&gt; any'.
  node_modules/typescript/lib/lib.webworker.d.ts(4332,13): error TS2403: Subsequent variable declarations must have the same type.  Variable 'location' must be of type 'Location', but here has type 'WorkerLocation'.
  node_modules/typescript/lib/lib.webworker.d.ts(4333,13): error TS2403: Subsequent variable declarations must have the same type.  Variable 'onerror' must be of type 'OnErrorEventHandlerNonNull', but here has type '(this: DedicatedWorkerGlobalScope, ev: ErrorEvent) =&gt; any'.
  node_modules/typescript/lib/lib.webworker.d.ts(4335,13): error TS2403: Subsequent variable declarations must have the same type.  Variable 'self' must be of type 'Window', but here has type 'WorkerGlobalScope'.
  node_modules/typescript/lib/lib.webworker.d.ts(4344,13): error TS2403: Subsequent variable declarations must have the same type.  Variable 'navigator' must be of type 'Navigator', but here has type 'WorkerNavigator'.
  </code></pre>
  
  <p>Here is my package.json file:</p>
  
  <pre><code>    {
    "name": "app-name",
    "version": "0.0.0",
    "scripts": {
      "ng": "ng",
      "start": "ng serve",
      "build": "ng build",
      "test": "ng test",
      "lint": "ng lint",
      "e2e": "ng e2e"
    },
    "private": true,
    "dependencies": {
      "@angular/animations": "^8.0.0",
      "@angular/cdk": "^8.0.0",
      "@angular/common": "^8.0.0",
      "@angular/compiler": "^8.0.0",
      "@angular/core": "^8.0.0",
      "@angular/fire": "^5.1.3",
      "@angular/forms": "^8.0.0",
      "@angular/material": "^8.0.0",
      "@angular/platform-browser": "^8.0.0",
      "@angular/platform-browser-dynamic": "^8.0.0",
      "@angular/router": "^8.0.0",
      "bootstrap": "^4.3.1",
      "classlist.js": "^1.1.20150312",
      "core-js": "^2.5.4",
      "firebase": "^5.11.1",
      "hammerjs": "^2.0.8",
      "material-design-icons": "^3.0.1",
      "rxjs": "^6.5.2",
      "save": "^2.3.3",
      "smoothscroll-polyfill": "^0.4.3",
      "tslib": "^1.9.0",
      "web-animations-js": "github:angular/web-animations-js#release_pr208",
      "zone.js": "~0.9.1"
    },
    "devDependencies": {
      "@angular-devkit/build-angular": "~0.800.1",
      "@angular/cli": "^8.0.1",
      "@angular/compiler-cli": "^8.0.0",
      "@angular/language-service": "^8.0.0",
      "@types/jasmine": "~3.3.0",
      "@types/jasminewd2": "~2.0.6",
      "@types/node": "~12.0.3",
      "codelyzer": "^5.0.1",
      "jasmine-core": "~3.3.0",
      "jasmine-spec-reporter": "~4.2.1",
      "karma": "^4.0.1",
      "karma-chrome-launcher": "~2.2.0",
      "karma-coverage-istanbul-reporter": "~2.0.4",
      "karma-jasmine": "~2.0.1",
      "karma-jasmine-html-reporter": "^1.4.0",
      "protractor": "~5.4.1",
      "ts-node": "~7.0.1",
      "tslint": "~5.11.0",
      "typescript": "^3.4.5"
    }
  }
  </code></pre>
  
  <p>Thanks.</p>