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 

header31012 +
    format31012
  );
}
function validateOS2Table(os2, file) {
  file.pos = (file.start || 0) + os2.offset;
  const version = file.getUint16();
  
  
  file.skip(60); 
  const selection = file.getUint16();
  if (version < 4 && selection & 0x0300) {
    return false;
  }
  const firstChar = file.getUint16();
  const lastChar = file.getUint16();
  if (firstChar > lastChar) {
    return false;
  }
  file.skip(6); 
  const usWinAscent = file.getUint16();
  if (usWinAscent === 0) {
    
    return false;
  }
  
  os2.data[8] = os2.data[9] = 0; 
  return true;
}
function createOS2Table(properties, charstrings, override) {