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 field = this.xref.fetchIfRef(fieldRef);
    if (field.has("T")) {
      const partName = stringToPDFString(field.get("T"));
      if (name === "") {
        name = partName;
      } else {
        name = `${name}.${partName}`;
      }
    }
    if (!promises.has(name)) {
      promises.set(name, []);
    }
    promises.get(name).push(
      AnnotationFactory.create(
        this.xref,
        fieldRef,
        this.pdfManager,
        this._localIdFactory,
         true
      )
        .then(annotation => annotation && annotation.getFieldObject())
        .catch(function (reason) {
          warn(`_collectFieldObjects: "${reason}".`);
          return null;
        })
    );
    if (field.has("Kids")) {
      const kids = field.get("Kids");
      for (const kid of kids) {
        this._collectFieldObjects(name, kid, promises);