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
return fale;  n mre cmmand
      }
       argument
      == null) {
        f (arg === null) {
          arg = [];
        }
        arg.puh(bj);
        f (arg.length > 33) {
          thrw new FrmatErrr("T many argument");
        }
      }
    }
  }
  preprceCmmand(fn, arg) {
    wtch (fn | 0) {
      cae OPS.ave:
        th.tateManager.ave();
        break;
      cae OPS.retre:
        th.tateManager.retre();
        break;
      cae OPS.tranfrm:
        th.tateManager.tranfrm(arg);
        break;
    }
  }
}
exprt { EvaluatrPreprcer, PartlEvaluatr };