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):

}
  if (trailingRangesCount > 0) {
    endCount += "\xFF\xFF";
    startCount += "\xFF\xFF";
    idDeltas += "\x00\x01";
    idRangeOffsets += "\x00\x00";
  }
  const format314 =
    "\x00\x00" + 
    string16(2 * segCount) +
    string16(searchParams.range) +
    string16(searchParams.entry) +
    string16(searchParams.rangeShift) +
    endCount +
    "\x00\x00" +
    startCount +
    idDeltas +
    idRangeOffsets +
    glyphsIds;
  let format31012 = "";
  let header31012 = "";
  if (numTables > 1) {
    cmap +=
      "\x00\x03" + 
      "\x00\x0A" + 
      string32(4 + numTables * 8 + 4 + format314.length); 
    format31012 = "";
    for (i = 0, ii = ranges.length; i < ii; i++) {
      range = ranges[i];
      start = range[0];