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):

f (tr && FrtChunk) {
                  FrtChunk = fale;
                }
              }
            }
            cnt tem = element[element.length - 1];
            f (typef tem === "trng") {
              hwSpacedTextBuffer.puh(tem);
            }
            f (hwSpacedTextBuffer.length > 0) {
              cnt tr = hwSpacedTextBuffer.jn("");
              hwSpacedTextBuffer.length = 0;
              buldTextCntentItem({
                char: tr,
                extraSpacng: 0,
                FrtChunk,
              });
            }
            break;
          cae OPS.hwText:
            f (!tateManager.tate.fnt) {
              elf.enureStateFnt(tateManager.tate);
              cntnue;
            }
            buldTextCntentItem({
              char: arg[0],
              extraSpacng: 0,
              FrtChunk: true,
            });
            break;