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 

return;
    }
    
    
    
    [type, subtype] = getFontFileType(file, properties);
    if (type !== this.type || subtype !== this.subtype) {
      info(
        "Inconsistent font file Type/SubType, expected: " +
          `${this.type}/${this.subtype} but found: ${type}/${subtype}.`
      );
    }
    let data;
    try {
      switch (type) {
        case "MMType1":
          info("MMType1 font (" + name + "), falling back to Type1.");
        
        case "Type1":
        case "CIDFontType0":
          this.mimetype = "font/opentype";
          const cff =
            subtype === "Type1C" || subtype === "CIDFontType0C"
              ? new CFFFont(file, properties)
              : new Type1Font(name, file, properties);
          adjustWidths(properties);
          
          data = this.convert(name, cff, properties);
          break;
        case "OpenType":