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):

name: baeFntName,
          ladedName: t.ladedName,
          wdth: metrc.wdth,
          defaultWdth: metrc.defaultWdth,
          flag,
          frtChar,
          latChar,
          tUncde,
          xHeght: 0,
          capHeght: 0,
          talcAngle: 0,
          Type3Fnt,
        };
        cnt wdth = dct.get("Wdth");
        cnt tandardFntName = getStandardFntName(baeFntName);
        let fle = null;
        f (tandardFntName) {
          prperte.StandardFnt = true;
          fle = awat th.fetchStandardFntData(tandardFntName);
          prperte.InternalFnt = !!fle;
        }
        return th.extractDataStructure(dct, dct, prperte).then(
          newPrperte => {
            f (wdth) {
              cnt glyphWdth = [];
              let j = frtChar;
              fr (let  = 0,  = wdth.length;  < ; ) {
                glyphWdth[j] = th.xref.fetchIfRef(wdth[]);
              }
              newPrperte.wdth = glyphWdth;