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
```
return this.appearance.dict.getAsync("Resources").then(resources => {
      if (!resources) {
        return undefined;
      }
      const objectLoader = new ObjectLoader(resources, keys, resources.xref);
      return objectLoader.load().then(function () {
        return resources;
      });
    });
  }
  getOperatorList(evaluator, task, renderForms, annotationStorage) {
    if (!this.appearance) {
      return Promise.resolve(new OperatorList());
    }
    const appearance = this.appearance;
    const data = this.data;
    const appearanceDict = appearance.dict;
    const resourcesPromise = this.loadResources([
      "ExtGState",
      "ColorSpace",
      "Pattern",
      "Shading",
      "XObject",
      "Font",
    ]);
    const bbox = appearanceDict.getArray("BBox") || [0, 0, 1, 1];
    const matrix = appearanceDict.getArray("Matrix") || [1, 0, 0, 1, 0, 0];
    const transform = getTransformMatrix(data.rect, bbox, matrix);
    return resourcesPromise.then(resources => {
      const opList = new OperatorList();