Attach (recommended) or Link to PDF file here:
https://guichet.public.lu/dam-assets/catalogue-formulaires/tva/tva-option-aic-pers-morales/tva-option-aic-pers-morale-DE.pdf

Configuration:
- Web browser and its version: Firefox Nightly 91.0a1 (2021-06-26) (64-bit)
- Operating system and its version: Windows 10.0.19043.1052
- PDF.js version: N/A

Steps to reproduce the problem:
1. enableXFA in Firefox Nightly
2. Open form

What is the expected behavior? (add screenshot)
Header image is scaled properly
![image](https://user-images.githubusercontent.com/7104454/123525954-905d1f00-d6a2-11eb-840e-be30eee395e1.png)

What went wrong? (add screenshot)
Image is scaled to fit
![image](https://user-images.githubusercontent.com/7104454/123525957-96530000-d6a2-11eb-9991-bf7f37c6f1a5.png)


const sweepAngle = (this.sweepAngle * Math.PI) / 180;
      const largeArc = this.sweepAngle - this.startAngle > 180 ? 1 : 0;
      const [x1, y1, x2, y2] = [
        50 * (1 + Math.cos(startAngle)),
        50 * (1 - Math.sin(startAngle)),
        50 * (1 + Math.cos(sweepAngle)),
        50 * (1 - Math.sin(sweepAngle)),
      ];
      arc = {
        name: "path",
        attributes: {
          xmlns: SVG_NS,
          d: `M ${x1} ${y1} A 50 50 0 ${largeArc} 0 ${x2} ${y2}`,
          vectorEffect: "non-scaling-stroke",
          style,
        },
      };
      Object.assign(attributes, {
        viewBox: "0 0 100 100",
        preserveAspectRatio: "none",
      });
    }
    return HTMLResult.success({
      name: "svg",
      children: [arc],
      attributes,
    });
  }
}
class Area extends XFAObject {