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 subtype = parameters.data.annotationType;
    switch (subtype) {
      case AnnotationType.LINK:
        return new LinkAnnotationElement(parameters);
      case AnnotationType.TEXT:
        return new TextAnnotationElement(parameters);
      case AnnotationType.WIDGET:
        const fieldType = parameters.data.fieldType;
        switch (fieldType) {
          case "Tx":
            return new TextWidgetAnnotationElement(parameters);
          case "Btn":
            if (parameters.data.radioButton) {
              return new RadioButtonWidgetAnnotationElement(parameters);
            } else if (parameters.data.checkBox) {
              return new CheckboxWidgetAnnotationElement(parameters);
            }
            return new PushButtonWidgetAnnotationElement(parameters);
          case "Ch":
            return new ChoiceWidgetAnnotationElement(parameters);
        }
        return new WidgetAnnotationElement(parameters);
      case AnnotationType.POPUP:
        return new PopupAnnotationElement(parameters);
      case AnnotationType.FREETEXT:
        return new FreeTextAnnotationElement(parameters);
      case AnnotationType.LINE:
        return new LineAnnotationElement(parameters);