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
for (let charCode = 0; charCode < 256; charCode++) {
            var glyphName, standardGlyphName;
            if (this.differences && charCode in this.differences) {
              glyphName = this.differences[charCode];
            } else if (
              charCode in baseEncoding &&
              baseEncoding[charCode] !== ""
            ) {
              glyphName = baseEncoding[charCode];
            } else {
              glyphName = StandardEncoding[charCode];
            }
            if (!glyphName) {
              continue;
            }
            
            standardGlyphName = recoverGlyphName(glyphName, glyphsUnicodeMap);
            var unicodeOrCharCode;
            if (cmapPlatformId === 3 && cmapEncodingId === 1) {
              unicodeOrCharCode = glyphsUnicodeMap[standardGlyphName];
            } else if (cmapPlatformId === 1 && cmapEncodingId === 0) {
              
              unicodeOrCharCode = MacRomanEncoding.indexOf(standardGlyphName);
            }
            for (let i = 0; i < cmapMappingsLength; ++i) {
              if (cmapMappings[i].charCode !== unicodeOrCharCode) {
                continue;
              }
              charCodeToGlyphId[charCode] = cmapMappings[i].glyphId;
              break;