Configuration:
- PDF.js version: 2.0.550

Steps to reproduce the problem:
1. Render document in SVG mode `renderMode="svg"`

What is the expected behavior? (add screenshot)
Rendering annotations same way as they rendered on canvas

What went wrong? (add screenshot)
```
Warning: Unimplemented operator beginAnnotations
Warning: Unimplemented operator endAnnotations
```
return !!this._transport._htmlForXfa;
  }
  /**
   * NOTE: This is (mostly) intended to support printing of XFA forms.
   *
   * @type {Object | null} An object representing a HTML tree structure
   *   to render the XFA, or `null` when no XFA form exists.
   */
  get allXfaHtml() {
    return this._transport._htmlForXfa;
  }
  /**
   * @param {number} pageNumber - The page number to get. The first page is 1.
   * @returns {Promise<PDFPageProxy>} A promise that is resolved with
   *   a {@link PDFPageProxy} object.
   */
  getPage(pageNumber) {
    return this._transport.getPage(pageNumber);
  }
  /**
   * @param {RefProxy} ref - The page reference.
   * @returns {Promise<number>} A promise that is resolved with the page index,
   *   starting from zero, that is associated with the reference.
   */
  getPageIndex(ref) {