code: function glFunctionArgToString(functionName, argumentIndex, value) {
    var funcInfo = glValidEnumContexts[functionName];
    if (funcInfo !== undefined) {
      if (funcInfo[argumentIndex]) {
        return glEnumToString(value);
      }
    }
    if (value === null) {
      return "null";
    } else if (value === undefined) {
      return "undefined";
    } else {
      return value.toString();
    }
  }
docs: Returns the string version of a WebGL argument.
  Attempts to convert enum arguments to strings.
  @param {string} functionName the name of the WebGL function.
  @param {number} argumentIndx the index of the argument.
  @param {*} value The value of the argument.
  @return {string} The value as a string.