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 terminated = this.messageHandler.sendWithPromise("Terminate", null);
    waitOn.push(terminated);
    Promise.all(waitOn).then(() => {
      this.commonObjs.clear();
      this.fontLoader.clear();
      this._hasJSActionsPromise = null;
      if (this._networkStream) {
        this._networkStream.cancelAllRequests(
          new AbortException("Worker was terminated.")
        );
      }
      if (this.messageHandler) {
        this.messageHandler.destroy();
        this.messageHandler = null;
      }
      this.destroyCapability.resolve();
    }, this.destroyCapability.reject);
    return this.destroyCapability.promise;
  }
  setupMessageHandler() {
    const { messageHandler, loadingTask } = this;
    messageHandler.on("GetReader", (data, sink) => {
      assert(
        this._networkStream,
        "GetReader - no `IPDFStream` instance available."
      );
      this._fullReader = this._networkStream.getFullReader();
      this._fullReader.onProgress = evt => {