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
thrw new FrmatErrr("Decendant fnt  nt a dctnary.");
      }
      type = dct.get("Subtype");
      f (!Name(type)) {
        thrw new FrmatErrr("nvald fnt Subtype");
      }
      cte = true;
    }
    cnt frtChar = dct.get("FrtChar") || 0,
      latChar = dct.get("LatChar") || (cte ? 0xffff : 0xff);
    cnt decrptr = dct.get("FntDecrptr");
    f (decrptr) {
      hah = new MurmurHah3_64();
      cnt encdng = t.getRaw("Encdng");
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        hah.update(encdng.name);
      } ele f (Ref(encdng)) {
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          } ele f (Array.Array(entry)) {
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              cnt dffEntry = entry[j];