Minor clean up.

src/core/Geometry.js

@@ -865,11 +865,11 @@ THREE.Geometry.prototype = {
 
 	sortFacesByMaterialIndex: function () {
 
-		// tag faces
-
 		var faces = this.faces;
 		var length = faces.length;
 
+		// tag faces
+
 		for ( var i = 0; i < length; i ++ ) {
 
 			faces[ i ]._id = i;