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 BACKGROUND_ENLIGHT = 0.7;
    const wrapper = document.createElement("div");
    wrapper.className = "popupWrapper";
    
    
    
    
    this.hideElement = this.hideWrapper ? wrapper : this.container;
    this.hideElement.setAttribute("hidden", true);
    const popup = document.createElement("div");
    popup.className = "popup";
    const color = this.color;
    if (color) {
      
      const r = BACKGROUND_ENLIGHT * (255 - color[0]) + color[0];
      const g = BACKGROUND_ENLIGHT * (255 - color[1]) + color[1];
      const b = BACKGROUND_ENLIGHT * (255 - color[2]) + color[2];
      popup.style.backgroundColor = Util.makeHexColor(r | 0, g | 0, b | 0);
    }
    const title = document.createElement("h1");
    title.textContent = this.title;
    popup.appendChild(title);
    
    
    
    const dateObject = PDFDateString.toDateObject(this.modificationDate);
    if (dateObject) {
      const modificationDate = document.createElement("span");
      modificationDate.textContent = "{{date}}, {{time}}";
      modificationDate.dataset.l10nId = "annotation_date_string";