When using viewer.js code in an iframe (`web/viewer.html?file=my.pdf"`) and getting a load error like `Error: file origin does not match viewer's` how do I catch this error?  The console reports `app.js:2140 Uncaught (in promise) Error: file origin does not match viewer's`.  I have setup the load listener and am using the `PDFViewerApplication.initializedPromise`.  I was hoping the `PDFViewerApplication.initializedPromise` would reject, but it does not.  I could not find an eventbus event to listen to specifically for load errors either.

I would like to programmatically detect such load errors and dynamically remove the iframe hosting the pdf viewer and instead replace it with my own error messaging.  I can't figure out how to do that.

Configuration:
- Any, but testing on Chrome 97.0.4692.71 64-bit
- Ubuntu 20.04
- PDF.js version:  v2.12.313
- Is a browser extension: No

Steps to reproduce the problem:
1.  Purposely try to load a PDF in a way that would cause the `app.js:2140 Uncaught (in promise) Error: file origin does not match viewer's` error.
linkService: pdfLinkService,
      eventBus,
    });
    this.findController = findController;
    const pdfScriptingManager = new PDFScriptingManager({
      eventBus,
      sandboxBundleSrc:
        typeof PDFJSDev === "undefined" ||
        PDFJSDev.test("!PRODUCTION || GENERIC || CHROME")
          ? AppOptions.get("sandboxBundleSrc")
          : null,
      scriptingFactory: externalServices,
      docPropertiesLookup: this._scriptingDocProperties.bind(this),
    });
    this.pdfScriptingManager = pdfScriptingManager;
    const container = appConfig.mainContainer;
    const viewer = appConfig.viewerContainer;
    this.pdfViewer = new PDFViewer({
      container,
      viewer,
      eventBus,
      renderingQueue: pdfRenderingQueue,
      linkService: pdfLinkService,
      downloadManager,
      findController,
      scriptingManager:
        AppOptions.get("enableScripting") && pdfScriptingManager,
      renderer: AppOptions.get("renderer"),
      l10n: this.l10n,
      textLayerMode: AppOptions.get("textLayerMode"),