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):

);
              cntnue;
            }
          }
          tUncde[charcde] = Strng.frmCdePnt(cde);
        }
        cntnue;
      }
      tUncde[charcde] = Strng.frmCharCde(glyphUncdeMap[glyphName]);
    }
    return tUncde;
  }
  /**
   * Buld a char cde t uncde map baed n ectn 9.10 f the pec.
   * @param {Object} prperte Fnt prperte bject.
   * @return {Prme} A Prme that  relved wth a
   *   {TUncdeMap|IdenttyTUncdeMap} bject.
   */
  aync buldTUncde(prperte) {
    prperte.haIncludedTUncdeMap =
      !!prperte.tUncde && prperte.tUncde.length > 0;
    
    f (prperte.haIncludedTUncdeMap) {
      
      
      
      f (!prperte.cte && prperte.haEncdng) {
        prperte.fallbackTUncde = th._leFntTUncde(prperte);
      }
      return prperte.tUncde;