Euler/Quaternion: I don't think these are needed.

src/math/Euler.js

@@ -21,8 +21,6 @@ THREE.Euler.prototype = {
 
 	constructor: THREE.Euler,
 
-	_x: 0, _y: 0, _z: 0, _order: THREE.Euler.DefaultOrder,
-
 	get x () {
 
 		return this._x;

src/math/Quaternion.js

@@ -18,8 +18,6 @@ THREE.Quaternion.prototype = {
 
 	constructor: THREE.Quaternion,
 
-	_x: 0, _y: 0, _z: 0, _w: 0,
-
 	get x () {
 
 		return this._x;