code: function nextPhase(priv) {
    setPhase(priv, PHASE_VALUES[(PHASE_VALUES.indexOf(priv.phase) + 1) % PHASE_VALUES.length]);
  }
docs: Switches phase to next one.
  
  This method is automatically invoked each time a transition ends
  on DOM element added as phase trigger.
  
  @fqn Phaser.prototype.nextPhase