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">


let container = this.container;
    if (this.quadrilaterals) {
      trigger = trigger || this.quadrilaterals;
      container = this.quadrilaterals[0];
    }
    
    if (!trigger) {
      trigger = document.createElement("div");
      trigger.style.height = container.style.height;
      trigger.style.width = container.style.width;
      container.appendChild(trigger);
    }
    const popupElement = new PopupElement({
      container,
      trigger,
      color: data.color,
      title: data.title,
      modificationDate: data.modificationDate,
      contents: data.contents,
      hideWrapper: true,
    });
    const popup = popupElement.render();
    
    popup.style.left = container.style.width;
    container.appendChild(popup);
  }
  /**
   * Render the quadrilaterals of the annotation.
   *