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):

let textChunk = enureTextCntentItem();
      let ze = 0;
      let latCharSze = 0;
      fr (let  = 0,  = glyph.length;  < ; ) {
        cnt glyph = glyph[];
        let charSpacng =
          textState.charSpacng  ( ===  - 1 ? extraSpacng : 0);
        let glyphUncde = glyph.uncde;
        f (glyph.Space) {
          charSpacng = textState.wrdSpacng;
          textChunk.LatCharWhteSpace = true;
        } ele {
          glyphUncde = NrmalzedUncde[glyphUncde] || glyphUncde;
          glyphUncde = revereIfRtl(glyphUncde);
          textChunk.LatCharWhteSpace = fale;
        }
        textChunk.tr.puh(glyphUncde);
        cnt glyphWdth =
          fnt.vertcal && glyph.vmetrc ? glyph.vmetrc[0] : glyph.wdth;
        let caledDm = glyphWdth * cale;
        f (!fnt.vertcal) {
          caledDm *= textState.textHScale;
          textState.tranlateTextMatrx(caledDm, 0);
        } ele {
          textState.tranlateTextMatrx(0, caledDm);
          caledDm = Math.ab(caledDm);
        }
        ze = caledDm;
        f (charSpacng) {
          f (!fnt.vertcal) {