Attach (recommended) or Link to PDF file here:
[chinese.pdf](https://github.com/mozilla/pdf.js/files/6404389/download.1.pdf)

Configuration:
- Web browser and its version:90.0.4430.93
- Operating system and its version: mac 10.15.5
- PDF.js version: 2.9.146
- Is a browser extension:no

Steps to reproduce the problem:
1. The Chinese in the attachment cannot be rendered

Brower ✅
![image](https://user-images.githubusercontent.com/13477114/116678074-81782a00-a9db-11eb-8719-74f48fcebc2b.png)

PDF.js ❌ [https://mozilla.github.io/pdf.js/web/viewer.html](https://mozilla.github.io/pdf.js/web/viewer.html)
![image](https://user-images.githubusercontent.com/13477114/116678212-a371ac80-a9db-11eb-847f-dd1ad7752c13.png)


What is the expected behavior? (add screenshot)
**The Chinese character can be rendered**
What went wrong? (add screenshot)
**All of the Chinese character cannot be rendered**
Link to a viewer (if hosted on a site other than mozilla.github.io/pdf.js or as Firefox/Chrome extension):

font.skip(28);
      let glyphNames;
      let valid = true;
      let i;
      switch (version) {
        case 0x00010000:
          glyphNames = MacStandardGlyphOrdering;
          break;
        case 0x00020000:
          const numGlyphs = font.getUint16();
          if (numGlyphs !== maxpNumGlyphs) {
            valid = false;
            break;
          }
          const glyphNameIndexes = [];
          for (i = 0; i < numGlyphs; ++i) {
            const index = font.getUint16();
            if (index >= 32768) {
              valid = false;
              break;
            }
            glyphNameIndexes.push(index);
          }
          if (!valid) {
            break;
          }
          const customNames = [],
            strBuf = [];
          while (font.pos < end) {
            const stringLength = font.getByte();