Removed completed webkit implementation compatibility TODO

Author: pavle-goloskokovic

v3/src/sound/webaudio/WebAudioSound.js

@@ -3,8 +3,6 @@ var BaseSound = require('../BaseSound');
 var SoundEvent = require('../SoundEvent');
 var SoundValueEvent = require('../SoundValueEvent');
 //  Phaser.Sound.WebAudioSound
-// TODO support webkitAudioContext implementation differences
-// https://developer.mozilla.org/en-US/docs/Web/API/Web_Audio_API/Porting_webkitAudioContext_code_to_standards_based_AudioContext
 var WebAudioSound = new Class({
     Extends: BaseSound,
     initialize: function WebAudioSound(manager, key, config) {