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 

baseFontCharCode,
            accentFontCharCode,
            accentOffset,
          };
        }
      }
      properties.seacMap = seacMap;
    }
    const unitsPerEm = 1 / (properties.fontMatrix || FONT_IDENTITY_MATRIX)[0];
    const builder = new OpenTypeFileBuilder("\x4F\x54\x54\x4F");
    
    builder.addTable("CFF ", font.data);
    
    builder.addTable("OS/2", createOS2Table(properties, newCharCodeToGlyphId));
    
    builder.addTable("cmap", createCmapTable(newCharCodeToGlyphId, numGlyphs));
    
    builder.addTable(
      "head",
      "\x00\x01\x00\x00" + 
        "\x00\x00\x10\x00" + 
        "\x00\x00\x00\x00" + 
        "\x5F\x0F\x3C\xF5" + 
        "\x00\x00" + 
        safeString16(unitsPerEm) + 
        "\x00\x00\x00\x00\x9e\x0b\x7e\x27" + 
        "\x00\x00\x00\x00\x9e\x0b\x7e\x27" + 
        "\x00\x00" + 
        safeString16(properties.descent) + 
        "\x0F\xFF" +