#9735: Fixed copy method in THREE.Spherical (#9737)

src/math/Spherical.js

@@ -42,9 +42,9 @@ Spherical.prototype = {
 
 	copy: function ( other ) {
 
-		this.radius.copy( other.radius );
-		this.phi.copy( other.phi );
-		this.theta.copy( other.theta );
+		this.radius = other.radius;
+		this.phi = other.phi;
+		this.theta = other.theta;
 
 		return this;