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):

codes = range[2];
      let code = codes[0];
      for (j = 1, jj = codes.length; j < jj; ++j) {
        if (codes[j] !== codes[j - 1] + 1) {
          end = range[0] + j - 1;
          format31012 +=
            string32(start) + 
            string32(end) + 
            string32(code); 
          start = end + 1;
          code = codes[j];
        }
      }
      format31012 +=
        string32(start) + 
        string32(range[1]) + 
        string32(code); 
    }
    header31012 =
      "\x00\x0C" + 
      "\x00\x00" + 
      string32(format31012.length + 16) + 
      "\x00\x00\x00\x00" + 
      string32(format31012.length / 12); 
  }
  return (
    cmap +
    "\x00\x04" + 
    string16(format314.length + 4) + 
    format314 +