message: small optimization when partials list is []
diff: @@ -304,6 +304,10 @@ export class Oscillator extends Source<ToneOscillatorOptions> implements ToneOsc
  partialCount = this._partials.length + 1;
  this._partialCount = this._partials.length;
  periodicWaveSize = partialCount;
  + // if the partial count is 0, don't bother doing any computation
  + if (this._partials.length === 0 ) {
  + return [real, imag];
  + }
  } else {
  const partial = /^(sine|triangle|square|sawtooth)(\d+)$/.exec(type);
  if (partial) {
  