message: skipping FMSynth comparison when not on Chrome
diff: define(["Tone/instrument/FMSynth", "helper/Basic",
  - "helper/InstrumentTests", "helper/CompareToFile"],
  -function(FMSynth, Basic, InstrumentTest, CompareToFile) {
  + "helper/InstrumentTests", "helper/CompareToFile", "helper/Supports"],
  +function(FMSynth, Basic, InstrumentTest, CompareToFile, Supports) {
  describe("FMSynth", function(){
  Basic(FMSynth);
  InstrumentTest(FMSynth, "C4");
  + if (Supports.CHROME_AUDIO_RENDERING){
  it("matches a file", function(){
  return CompareToFile(function(){
  const synth = new FMSynth().toMaster();
  synth.triggerAttackRelease("G4", 0.1, 0.05);
  }, "fmSynth.wav");
  });
  + }
  context("API", function(){
  