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.
})
        .then(function () {
          
          
          
          
          pdfViewer.update();
        });
    });
    pagesPromise.then(
      () => {
        this._unblockDocumentLoadEvent();
        this._initializeAutoPrint(pdfDocument, openActionPromise);
      },
      reason => {
        this.l10n.get("loading_error").then(msg => {
          this._documentError(msg, { message: reason?.message });
        });
      }
    );
    onePageRendered.then(data => {
      this.externalServices.reportTelemetry({
        type: "pageInfo",
        timestamp: data.timestamp,
      });
      pdfDocument.getOutline().then(outline => {
        if (pdfDocument !== this.pdfDocument) {
          return; 
        }
        this.pdfOutlineViewer.render({ outline, pdfDocument });