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):

funcId = stack.pop();
          ttContext.functionsDefined[funcId] = { data, i };
        } else if (op === 0x2d) {
          
          if (inFDEF) {
            inFDEF = false;
            lastEndf = i;
          } else {
            pc = callstack.pop();
            if (!pc) {
              warn("TT: ENDF bad stack");
              ttContext.hintsValid = false;
              return;
            }
            funcId = functionsCalled.pop();
            data = pc.data;
            i = pc.i;
            ttContext.functionsStackDeltas[funcId] = stack.length - pc.stackTop;
          }
        } else if (op === 0x89) {
          
          if (inFDEF || inELSE) {
            warn("TT: nested IDEFs not allowed");
            tooComplexToFollowFunctions = true;
          }
          inFDEF = true;
          
          lastDeff = i;
        } else if (op === 0x58) {