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
```
* @property {boolean} destroyed - Whether the loading task is destroyed or not.
 * @property {function} [onPassword] - Callback to request a password if a wrong
 *   or no password was provided. The callback receives two parameters: a
 *   function that should be called with the new password, and a reason (see
 *   {@link PasswordResponses}).
 * @property {function} [onProgress] - Callback to be able to monitor the
 *   loading progress of the PDF file (necessary to implement e.g. a loading
 *   bar). The callback receives an {@link OnProgressParameters} argument.
 * @property {function} [onUnsupportedFeature] - Callback for when an
 *   unsupported feature is used in the PDF document. The callback receives an
 *   {@link UNSUPPORTED_FEATURES} argument.
 * @property {Promise<PDFDocumentProxy>} promise - Promise for document loading
 *   task completion.
 * @property {function} destroy - Abort all network requests and destroy
 *   the worker. Returns a promise that is resolved when destruction is
 *   completed.
 */
/**
 * @type {any}
 * @ignore
 */
const PDFDocumentLoadingTask = (function PDFDocumentLoadingTaskClosure() {
  let nextDocumentId = 0;
  /**
   * The loading task controls the operations required to load a PDF document
   * (such as network requests) and provides a way to listen for completion,
   * after which individual pages can be rendered.
   */
  
  class PDFDocumentLoadingTask {