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
glyphId,
            });
          }
        } else {
          warn("cmap table has unsupported format: " + format);
          return {
            platformId: -1,
            encodingId: -1,
            mappings: [],
            hasShortCmap: false,
          };
        }
        
        mappings.sort(function (a, b) {
          return a.charCode - b.charCode;
        });
        for (i = 1; i < mappings.length; i++) {
          if (mappings[i - 1].charCode === mappings[i].charCode) {
            mappings.splice(i, 1);
            i--;
          }
        }
        return {
          platformId: potentialTable.platformId,
          encodingId: potentialTable.encodingId,
          mappings,
          hasShortCmap,
        };
      }
      function sanitizeMetrics(