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
```
paintWidth,
        paintHeight,
      };
    }
    _createMaskCanvas(img) {
      const ctx = this.ctx;
      const width = img.width,
        height = img.height;
      const fillColor = this.current.fillColor;
      const isPatternFill = this.current.patternFill;
      const maskCanvas = this.cachedCanvases.getCanvas(
        "maskCanvas",
        width,
        height
      );
      const maskCtx = maskCanvas.context;
      putBinaryImageMask(maskCtx, img);
      
      
      
      
      const objToCanvas = ctx.mozCurrentTransform;
      let maskToCanvas = Util.transform(objToCanvas, [
        1 / width,
        0,
        0,
        -1 / height,
        0,
        0,
      ]);