Attach (recommended) or Link to PDF file here:
https://drive.google.com/open?id=1UjLxnFw2g3gn3tvNLRYLdmG6mFdFKCcr

Configuration:
- Web browser and its version: Chrome 77.0.3865.90
- Operating system and its version: Mac mojave 10.14.6
- PDF.js version: 2.3.194
- Is a browser extension: Nope

Steps to reproduce the problem:
1. Make sure to set `renderInteractiveForms` to `true`
2. The read-only form field(Sample title) doesn't honor it's proper font-size

What is the expected behavior?
<img width="862" alt="write" src="https://user-images.githubusercontent.com/4616548/66152094-4a009a80-e64b-11e9-81dc-178068055efa.png">

What went wrong?
<img width="842" alt="wrong" src="https://user-images.githubusercontent.com/4616548/66152100-4d942180-e64b-11e9-91a8-ad9caf451f98.png">


this.creationDate = isString(creationDate) ? creationDate : null;
  }
  _setDefaultAppearance({
    xref,
    extra,
    strokeColor,
    fillColor,
    blendMode,
    pointsCallback,
  }) {
    let minX = Number.MAX_VALUE;
    let minY = Number.MAX_VALUE;
    let maxX = Number.MIN_VALUE;
    let maxY = Number.MIN_VALUE;
    const buffer = ["q"];
    if (extra) {
      buffer.push(extra);
    }
    if (strokeColor) {
      buffer.push(`${strokeColor[0]} ${strokeColor[1]} ${strokeColor[2]} RG`);
    }
    if (fillColor) {
      buffer.push(`${fillColor[0]} ${fillColor[1]} ${fillColor[2]} rg`);
    }
    for (const points of this.data.quadPoints) {
      const [mX, MX, mY, MY] = pointsCallback(buffer, points);
      minX = Math.min(minX, mX);
      maxX = Math.max(maxX, MX);
      minY = Math.min(minY, mY);