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 

isTrueType
    ) {
      const { scaleFactors } = properties;
      const isGlyphLocationsLong = int16(
        tables.head.data[50],
        tables.head.data[51]
      );
      const glyphs = new GlyfTable({
        glyfTable: tables.glyf.data,
        isGlyphLocationsLong,
        locaTable: tables.loca.data,
        numGlyphs,
      });
      glyphs.scale(scaleFactors);
      const { glyf, loca, isLocationLong } = glyphs.write();
      tables.glyf.data = glyf;
      tables.loca.data = loca;
      if (isLocationLong !== !!isGlyphLocationsLong) {
        tables.head.data[50] = 0;
        tables.head.data[51] = isLocationLong ? 1 : 0;
      }
      const metrics = tables.hmtx.data;
      for (let i = 0; i < numGlyphs; i++) {
        const j = 4 * i;
        const advanceWidth = Math.round(
          scaleFactors[i] * int16(metrics[j], metrics[j + 1])
        );
        metrics[j] = (advanceWidth >> 8) & 0xff;
        metrics[j + 1] = advanceWidth & 0xff;
        const lsb = Math.round(