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
```
const storageEntry =
      annotationStorage && annotationStorage.get(this.data.id);
    if (storageEntry && storageEntry.hidden !== undefined) {
      return !storageEntry.hidden;
    }
    return this.viewable && !this._hasFlag(this.flags, AnnotationFlag.HIDDEN);
  }
  /**
   * Check if the annotation must be printed by taking into account
   * the value found in the annotationStorage which may have been set
   * through JS.
   *
   * @public
   * @memberof Annotation
   * @param {AnnotationStorage} [annotationStorage] - Storage for annotation
   */
  mustBePrinted(annotationStorage) {