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):

"\x01\xDF" + 
    "\x00\x31" + 
    "\x01\x02" + 
    "\x00\x00" + 
    "\x00\x00\x06" +
    String.fromCharCode(properties.fixedPitch ? 0x09 : 0x00) +
    "\x00\x00\x00\x00\x00\x00" + 
    string32(ulUnicodeRange1) + 
    string32(ulUnicodeRange2) + 
    string32(ulUnicodeRange3) + 
    string32(ulUnicodeRange4) + 
    "\x2A\x32\x31\x2A" + 
    string16(properties.italicAngle ? 1 : 0) + 
    string16(firstCharIndex || properties.firstChar) + 
    string16(lastCharIndex || properties.lastChar) + 
    string16(typoAscent) + 
    string16(typoDescent) + 
    "\x00\x64" + 
    string16(winAscent) + 
    string16(winDescent) + 
    "\x00\x00\x00\x00" + 
    "\x00\x00\x00\x00" + 
    string16(properties.xHeight) + 
    string16(properties.capHeight) + 
    string16(0) + 
    string16(firstCharIndex || properties.firstChar) + 
    "\x00\x03"
  ); 
}
function createPostTable(properties) {