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
var charCodeToGlyphId = Object.create(null);
  var glyphId, charCode, baseEncoding;
  var isSymbolicFont = !!(properties.flags & FontFlags.Symbolic);
  if (properties.baseEncodingName) {
    
    
    baseEncoding = getEncoding(properties.baseEncodingName);
    for (charCode = 0; charCode < baseEncoding.length; charCode++) {
      glyphId = glyphNames.indexOf(baseEncoding[charCode]);
      if (glyphId >= 0) {
        charCodeToGlyphId[charCode] = glyphId;
      } else {
        charCodeToGlyphId[charCode] = 0; 
      }
    }
  } else if (isSymbolicFont) {
    
    for (charCode in builtInEncoding) {
      charCodeToGlyphId[charCode] = builtInEncoding[charCode];
    }
  } else {
    
    
    baseEncoding = StandardEncoding;
    for (charCode = 0; charCode < baseEncoding.length; charCode++) {
      glyphId = glyphNames.indexOf(baseEncoding[charCode]);
      if (glyphId >= 0) {
        charCodeToGlyphId[charCode] = glyphId;
      } else {
        charCodeToGlyphId[charCode] = 0;