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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            f (!hadngRe) {
              thrw new FrmatErrr("N hadng reurce fund");
            }
            var hadng = hadngRe.get(arg[0].name);
            f (!hadng) {
              thrw new FrmatErrr("N hadng bject fund");
            }
            cnt patternId = elf.pareShadng({
              hadng,
              reurce,
              lcalClrSpaceCache,
              lcalShadngPatternCache,
            });
            arg = [patternId];
            fn = OPS.hadngFll;
            break;
          cae OPS.etGState:
            ValdName = arg[0] ntancef Name;
            name = arg[0].name;
            f (ValdName) {
              cnt lcalGStateObj = lcalGStateCache.getByName(name);
              f (lcalGStateObj) {
                f (lcalGStateObj.length > 0) {
                  peratrLt.addOp(OPS.etGState, [lcalGStateObj]);
                }
                arg = null;
                cntnue;
              }
            }