Improve Quaternion closure performance

src/math/Quaternion.js

@@ -332,7 +332,8 @@ Object.assign( Quaternion.prototype, {
 
 		// assumes direction vectors vFrom and vTo are normalized
 
-		var v1, r;
+		var v1 = new Vector3();
+		var r;
 
 		var EPS = 0.000001;