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
```
maskToCanvas = Util.transform(maskToCanvas, [1, 0, 0, 1, 0, -height]);
      const cord1 = Util.applyTransform([0, 0], maskToCanvas);
      const cord2 = Util.applyTransform([width, height], maskToCanvas);
      const rect = Util.normalizeRect([cord1[0], cord1[1], cord2[0], cord2[1]]);
      const drawnWidth = Math.ceil(rect[2] - rect[0]);
      const drawnHeight = Math.ceil(rect[3] - rect[1]);
      const fillCanvas = this.cachedCanvases.getCanvas(
        "fillCanvas",
        drawnWidth,
        drawnHeight,
        true
      );
      const fillCtx = fillCanvas.context;
      
      const offsetX = Math.min(cord1[0], cord2[0]);
      const offsetY = Math.min(cord1[1], cord2[1]);
      fillCtx.translate(-offsetX, -offsetY);
      fillCtx.transform.apply(fillCtx, maskToCanvas);
      
      const scaled = this._scaleImage(
        maskCanvas.canvas,
        fillCtx.mozCurrentTransformInverse
      );
      fillCtx.drawImage(
        scaled.img,
        0,
        0,
        scaled.img.width,
        scaled.img.height,
        0,