Attach (recommended) or Link to PDF file here:
[test.pdf](https://github.com/mozilla/pdf.js/files/6270827/test.pdf)
Configuration:
- Web browser and its version:chrome 89
- Operating system and its version:win10
- PDF.js version: 2.4/2.7/2.8 no working
- Is a browser extension: no 

What is the expected behavior? (add screenshot)
![image](https://user-images.githubusercontent.com/18545199/113852392-1ae26080-97cf-11eb-9dc9-0cecf52d267b.png)

What went wrong? (add screenshot)
![1617791294(1)](https://user-images.githubusercontent.com/18545199/113852355-10c06200-97cf-11eb-8672-598750f1093a.jpg)


console this log : **FormatError: TrueType Collection does not contain "DCWGQU+CambriaMath" font** 

any solution?thanks
++ifLevel;
          } else if (op === 0x1b) {
            
            inELSE = ifLevel;
          } else if (op === 0x59) {
            
            if (inELSE === ifLevel) {
              inELSE = 0;
            }
            --ifLevel;
          } else if (op === 0x1c) {
            
            if (!inFDEF && !inELSE) {
              var offset = stack[stack.length - 1];
              
              if (offset > 0) {
                i += offset - 1;
              }
            }
          }
          
          if (!inFDEF && !inELSE) {
            let stackDelta = 0;
            if (op <= 0x8e) {
              stackDelta = TTOpsStackDeltas[op];
            } else if (op >= 0xc0 && op <= 0xdf) {
              stackDelta = -1;
            } else if (op >= 0xe0) {
              stackDelta = -2;
            }