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
```
if (this.data.pushButton) {
      return super.getOperatorList(
        evaluator,
        task,
        false, 
        annotationStorage
      );
    }
    if (annotationStorage) {
      const storageEntry = annotationStorage.get(this.data.id);
      const value = storageEntry && storageEntry.value;
      if (value === undefined) {
        return super.getOperatorList(
          evaluator,
          task,
          renderForms,
          annotationStorage
        );