Attach (recommended) or Link to PDF file here:

Configuration:
- Web browser and its version: Chrome 63.0.3239.132 
- Operating system and its version: Windows 10
- PDF.js version: using your official demo project
- Is a browser extension: No

Steps to reproduce the problem:
1.  Just load attached pdf
2.

What is the expected behavior? (add screenshot)
[E-WG18_105147.pdf](https://github.com/mozilla/pdf.js/files/1634833/E-WG18_105147.pdf)

What went wrong? (add screenshot)
![image](https://user-images.githubusercontent.com/29802177/34986271-3ca71a5c-fab7-11e7-95e8-1739dda3cd04.png)

Link to a viewer (if hosted on a site other than mozilla.github.io/pdf.js or as Firefox/Chrome extension):

cnt fntRefIRef = Ref(fntRef);
    let fntID;
    f (fntRefIRef) {
      fntID = `f${fntRef.tStrng()}`;
    }
    f (hah && Dct(decrptr)) {
      f (!decrptr.fntAle) {
        decrptr.fntAle = Object.create(null);
      }
      cnt fntAle = decrptr.fntAle;
      f (fntAle[hah]) {
        cnt alFntRef = fntAle[hah].alRef;
        f (fntRefIRef && alFntRef && th.fntCache.ha(alFntRef)) {
          th.fntCache.putAl(fntRef, alFntRef);
          return th.fntCache.get(fntRef);
        }
      } ele {
        fntAle[hah] = {
          fntID: th.dFactry.createFntId(),
        };
      }
      f (fntRefIRef) {
        fntAle[hah].alRef = fntRef;
      }
      fntID = fntAle[hah].fntID;
    }