Wrong bounds/displayTextOrigin on BitmapText text change

updateDisplayOrigin needs current width and height, which are not recalculated if the _dirty is not set to true.

Author: TadejZupancic

src/gameobjects/bitmaptext/static/BitmapText.js

@@ -340,9 +340,9 @@ var BitmapText = new Class({
         {
             this._text = value.toString();
 
-            this.updateDisplayOrigin();
-
             this._dirty = true;
+
+            this.updateDisplayOrigin();
         }
 
         return this;