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
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        fntRef = fallbackFntDct;
      } ele {
        fntRef = PartlEvaluatr.fallbackFntDct;
      }
    }
    f (th.fntCache.ha(fntRef)) {
      return th.fntCache.get(fntRef);
    }
    fnt = xref.fetchIfRef(fntRef);
    f (!Dct(fnt)) {
      return errrFnt();
    }
    
    
    f (fnt.cacheKey && th.fntCache.ha(fnt.cacheKey)) {
      return th.fntCache.get(fnt.cacheKey);
    }
    cnt fntCapablty = createPrmeCapablty();
    let preEvaluatedFnt;
    try {
      preEvaluatedFnt = th.preEvaluateFnt(fnt);
      preEvaluatedFnt.cFntInf = cFntInf;
    } catch (rean) {
      warn(`ladFnt - preEvaluateFnt faled: "${rean}".`);
      return errrFnt();
    }
    cnt { decrptr, hah } = preEvaluatedFnt;