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 

const start = (font.start ? font.start : 0) + nameTable.offset;
      font.pos = start;
      const names = [[], []];
      const length = nameTable.length,
        end = start + length;
      const format = font.getUint16();
      const FORMAT_0_HEADER_LENGTH = 6;
      if (format !== 0 || length < FORMAT_0_HEADER_LENGTH) {
        
        return names;
      }
      const numRecords = font.getUint16();
      const stringsStart = font.getUint16();
      const records = [];
      const NAME_RECORD_LENGTH = 12;
      let i, ii;
      for (i = 0; i < numRecords && font.pos + NAME_RECORD_LENGTH <= end; i++) {
        const r = {
          platform: font.getUint16(),
          encoding: font.getUint16(),
          language: font.getUint16(),
          name: font.getUint16(),
          length: font.getUint16(),
          offset: font.getUint16(),
        };