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 transform = this.ctx.mozCurrentTransform;
      return [
        transform[0] * x + transform[2] * y + transform[4],
        transform[1] * x + transform[3] * y + transform[5],
      ];
    }
    isContentVisible() {
      for (let i = this.markedContentStack.length - 1; i >= 0; i--) {
        if (!this.markedContentStack[i].visible) {
          return false;
        }
      }
      return true;
    }
  }
  for (const op in OPS) {
    CanvasGraphics.prototype[OPS[op]] = CanvasGraphics.prototype[op];
  }
  return CanvasGraphics;
})();
export { CanvasGraphics };