Attach (recommended) or Link to PDF file here:
[双引号不正常.pdf](https://github.com/mozilla/pdf.js/files/3533108/default.pdf)


Configuration:
- Web browser and its version:  IE11 , chrome 
- Operating system and its version:  win7
- PDF.js version:  master
- Is a browser extension: nothing 
teps to reproduce the problem:
1. viewer.html web  online preview


What is the expected behavior? (add screenshot)
Displayed in normal characters.

What went wrong? (add screenshot)
![20190823143813](https://user-images.githubusercontent.com/6269307/63571860-062e6600-c5b4-11e9-9fff-75d65cf6bade.png)

Not only the two characters I took screenshots, but also a lot of garbled Chinese punctuation. For example, the Chinese 《》 symbol. But these garbled characters only appear in some specific very old pdf files.

Link to a viewer (if hosted on a site other than mozilla.github.io/pdf.js or as Firefox/Chrome extension):nothing 

segments[segIndex].start = file.getUint16();
        }
        for (segIndex = 0; segIndex < segCount; segIndex++) {
          segments[segIndex].delta = file.getUint16();
        }
        let offsetsCount = 0,
          offsetIndex;
        for (segIndex = 0; segIndex < segCount; segIndex++) {
          segment = segments[segIndex];
          const rangeOffset = file.getUint16();
          if (!rangeOffset) {
            segment.offsetIndex = -1;
            continue;
          }
          offsetIndex = (rangeOffset >> 1) - (segCount - segIndex);
          segment.offsetIndex = offsetIndex;
          offsetsCount = Math.max(
            offsetsCount,
            offsetIndex + segment.end - segment.start + 1
          );
        }
        const offsets = [];
        for (j = 0; j < offsetsCount; j++) {
          offsets.push(file.getUint16());
        }
        for (segIndex = 0; segIndex < segCount; segIndex++) {
          segment = segments[segIndex];
          start = segment.start;
          const end = segment.end;
          const delta = segment.delta;