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
```
handler,
    task,
    normalizeWhitespace,
    includeMarkedContent,
    sink,
    combineTextItems,
  }) {
    const contentStreamPromise = this.getContentStream();
    const resourcesPromise = this.loadResources([
      "ExtGState",
      "Font",
      "Properties",
      "XObject",
    ]);
    const dataPromises = Promise.all([contentStreamPromise, resourcesPromise]);
    return dataPromises.then(([contentStream]) => {
      const partialEvaluator = new PartialEvaluator({
        xref: this.xref,
        handler,
        pageIndex: this.pageIndex,
        idFactory: this._localIdFactory,
        fontCache: this.fontCache,
        builtInCMapCache: this.builtInCMapCache,
        standardFontDataCache: this.standardFontDataCache,