title: VS Code - Angular: Experimental support for decorators Warning
body: <p>In an Angular (v10) project creating a blank file (sync.service.ts) and adding this code:</p>
  <pre><code>import { Injectable } from '@angular/core';
  
  @Injectable({
      providedIn: 'root'
  })
  export class SyncService {
  
  }
  </code></pre>
  <p>gives this warning:</p>
  <pre><code>Experimental support for decorators is a feature that is subject to change in a future release. Set the 'experimentalDecorators' option in your 'tsconfig' or 'jsconfig' to remove this warning.
  </code></pre>
  <p>I opened a random file (tag-cloud.component.ts) and added an import statement:</p>
  <pre><code>import { SyncService } from '../../services/sync.service';
  </code></pre>
  <p>The warning goes away. But the warning message shouldn't appear at all because of:</p>
  <pre><code>@Injectable({
      providedIn: 'root'
  })
  </code></pre>
  <p>Please see the gif below. Is this a bug?</p>
  <p><a href="https://i.stack.imgur.com/MSG2V.gif" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/MSG2V.gif" alt="enter image description here" /></a></p>
  <pre><code>Version: 1.47.1
  Commit: 485c41f9460bdb830c4da12c102daff275415b53
  Date: 2020-07-14T00:13:57.513Z
  Electron: 7.3.2
  Chrome: 78.0.3904.130
  Node.js: 12.8.1
  V8: 7.8.279.23-electron.0
  OS: Linux x64 5.4.0-40-generic
  </code></pre>