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">


if (!this.downloadManager) {
      warn("Download cannot be started due to unavailable download manager");
      return;
    }
    this.downloadManager.downloadData(this.content, this.filename, "");
  }
}
/**
 * @typedef {Object} AnnotationLayerParameters
 * @property {PageViewport} viewport
 * @property {HTMLDivElement} div
 * @property {Array} annotations
 * @property {PDFPage} page
 * @property {IPDFLinkService} linkService
 * @property {DownloadManager} downloadManager
 * @property {string} [imageResourcesPath] - Path for image resources, mainly
 *   for annotation icons. Include trailing slash.
 * @property {boolean} renderInteractiveForms
 * @property {boolean} [enableScripting] - Enable embedded script execution.
 * @property {boolean} [hasJSActions] - Some fields have JS actions.
 *   The default value is `false`.
 */
class AnnotationLayer {