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 name = event.target.name;
      for (const checkbox of document.getElementsByName(name)) {
        if (checkbox !== event.target) {
          checkbox.checked = false;
          storage.setValue(
            checkbox.parentNode.getAttribute("data-annotation-id"),
            { value: false }
          );
        }
      }
      storage.setValue(id, { value: event.target.checked });
    });
    if (this.enableScripting && this.hasJSActions) {
      element.addEventListener("updatefromsandbox", event => {
        const { detail } = event;
        const actions = {
          value() {
            event.target.checked = detail.value !== "Off";
            storage.setValue(id, { value: event.target.checked });
          },
          focus() {
            setTimeout(() => event.target.focus({ preventScroll: false }), 0);
          },
          hidden() {
            event.target.style.visibility = detail.hidden
              ? "hidden"
              : "visible";
            storage.setValue(id, { hidden: detail.hidden });
          },
          editable() {