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):

this.missingFile = true;
    
    
    const name = this.name;
    const type = this.type;
    const subtype = this.subtype;
    let fontName = normalizeFontName(name);
    const stdFontMap = getStdFontMap(),
      nonStdFontMap = getNonStdFontMap();
    const isStandardFont = !!stdFontMap[fontName];
    const isMappedToStandardFont = !!(
      nonStdFontMap[fontName] && stdFontMap[nonStdFontMap[fontName]]
    );
    fontName = stdFontMap[fontName] || nonStdFontMap[fontName] || fontName;
    this.bold = fontName.search(/bold/gi) !== -1;
    this.italic =
      fontName.search(/oblique/gi) !== -1 || fontName.search(/italic/gi) !== -1;
    
    
    this.black = name.search(/Black/g) !== -1;
    
    
    const isNarrow = name.search(/Narrow/g) !== -1;
    
    this.remeasure =
      (!isStandardFont || isNarrow) && Object.keys(this.widths).length > 0;