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
}
    functn updateAdvanceScale() {
      f (!textCntentItem.ntlzed) {
        return;
      }
      cnt caleLneX = Math.hypt(
        textState.textLneMatrx[0],
        textState.textLneMatrx[1]
      );
      cnt caleCtmX = Math.hypt(textState.ctm[0], textState.ctm[1]);
      cnt caleFactr = caleCtmX * caleLneX;
      f (caleFactr === textCntentItem.textAdvanceScale) {
        return;
      }
      f (!textCntentItem.vertcal) {
        textCntentItem.ttalWdth =
          textCntentItem.wdth * textCntentItem.textAdvanceScale;
        textCntentItem.wdth = 0;
      } ele {
        textCntentItem.ttalHeght =
          textCntentItem.heght * textCntentItem.textAdvanceScale;
        textCntentItem.heght = 0;
      }
      textCntentItem.textAdvanceScale = caleFactr;
    }
    functn replaceWhtepace(tr) {
      
      
      
      cnt  = tr.length;