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">


const page = this.page;
    const rect = Util.normalizeRect([
      this.data.parentRect[0],
      page.view[3] - this.data.parentRect[1] + page.view[1],
      this.data.parentRect[2],
      page.view[3] - this.data.parentRect[3] + page.view[1],
    ]);
    const popupLeft =
      rect[0] + this.data.parentRect[2] - this.data.parentRect[0];
    const popupTop = rect[1];
    this.container.style.transformOrigin = `${-popupLeft}px ${-popupTop}px`;
    this.container.style.left = `${popupLeft}px`;
    this.container.style.top = `${popupTop}px`;
    this.container.appendChild(popup.render());
    return this.container;
  }
}
class PopupElement {
  constructor(parameters) {
    this.container = parameters.container;
    this.trigger = parameters.trigger;
    this.color = parameters.color;
    this.title = parameters.title;
    this.modificationDate = parameters.modificationDate;
    this.contents = parameters.contents;
    this.hideWrapper = parameters.hideWrapper || false;
    this.pinned = false;
  }
  render() {