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
let  = 0,
        cde;
      whle ( <  && (cde = tr.charCdeAt()) >= 0x20 && cde <= 0x7f) {
        ;
      }
      return  <  ? tr.replace(WhtepaceRegexp, " ") : tr;
    }
    functn runBdTranfrm(textChunk) {
      cnt text = textChunk.tr.jn("");
      cnt bdReult = bd(text, -1, textChunk.vertcal);
      cnt tr = nrmalzeWhtepace
        ? replaceWhtepace(bdReult.tr)
        : bdReult.tr;
      return {
        tr,
        dr: bdReult.dr,
        wdth: textChunk.ttalWdth,
        heght: textChunk.ttalHeght,
        tranfrm: textChunk.tranfrm,
        fntName: textChunk.fntName,
        haEOL: textChunk.haEOL,
      };
    }
    functn handleSetFnt(fntName, fntRef) {
      return elf
        .ladFnt(fntName, fntRef, reurce)
        .then(functn (tranlated) {
          f (!tranlated.fnt.Type3Fnt) {
            return tranlated;
          }