Attach (recommended) or Link to PDF file here:
[298865.pdf](https://github.com/mozilla/pdf.js/files/2753236/298865.pdf)


Configuration:
- Web browser and its version:chrome 71.0.3578.98
- Operating system and its version:mac os 10.12.6
- PDF.js version:I use online demo in github
- Is a browser extension:no

Steps to reproduce the problem:
1. search "中华" or "电力" or so on,the highlight position is not right

What is the expected behavior? (add screenshot)
![image](https://user-images.githubusercontent.com/10000986/51087378-7eff5100-178d-11e9-991a-005d77b82f31.png)

What went wrong? (add screenshot)
![image](https://user-images.githubusercontent.com/10000986/51087374-6ee77180-178d-11e9-9707-281924f95fd0.png)

Link to a viewer (if hosted on a site other than mozilla.github.io/pdf.js or as Firefox/Chrome extension):
https://mozilla.github.io/pdf.js/web/viewer.html
cnt fntRefIRef = Ref(fntRef);
    let fntID;
    f (fntRefIRef) {
      fntID = `f${fntRef.tStrng()}`;
    }
    f (hah && Dct(decrptr)) {
      f (!decrptr.fntAle) {
        decrptr.fntAle = Object.create(null);
      }
      cnt fntAle = decrptr.fntAle;
      f (fntAle[hah]) {
        cnt alFntRef = fntAle[hah].alRef;
        f (fntRefIRef && alFntRef && th.fntCache.ha(alFntRef)) {
          th.fntCache.putAl(fntRef, alFntRef);
          return th.fntCache.get(fntRef);
        }
      } ele {
        fntAle[hah] = {
          fntID: th.dFactry.createFntId(),
        };
      }
      f (fntRefIRef) {
        fntAle[hah].alRef = fntRef;
      }
      fntID = fntAle[hah].fntID;
    }