jsdoc fix.

Author: photonstorm

src/physics/arcade/World.js

@@ -272,7 +272,7 @@ Phaser.Physics.Arcade.prototype = {
     * @method Phaser.Physics.Arcade#overlap
     * @param {Phaser.Sprite|Phaser.Group|Phaser.Particles.Emitter|array} object1 - The first object or array of objects to check. Can be Phaser.Sprite, Phaser.Group or Phaser.Particles.Emitter.
     * @param {Phaser.Sprite|Phaser.Group|Phaser.Particles.Emitter|array} object2 - The second object or array of objects to check. Can be Phaser.Sprite, Phaser.Group or Phaser.Particles.Emitter.
-    * @param {function} [overlapCallback=null] - An optional callback function that is called if the objects overlap. The two objects will be passed to this function in the same order in which you specified them.
+    * @param {function} [overlapCallback=null] - An optional callback function that is called if the objects overlap. The two objects will be passed to this function in the same order in which you specified them.  The two objects will be passed to this function in the same order in which you specified them, unless you are checking Group vs. Sprite, in which case Sprite will always be the first parameter.
     * @param {function} [processCallback=null] - A callback function that lets you perform additional checks against the two objects if they overlap. If this is set then overlapCallback will only be called if processCallback returns true.
     * @param {object} [callbackContext] - The context in which to run the callbacks.
     * @return {boolean} True if an overlap occurred otherwise false.