give Popup an 'updatePosition()' function that allows it to re-position itself. This will be used for zoom changes.

git-svn-id: http://svn.openlayers.org/trunk/openlayers@350 dc9f47b5-9b13-0410-9fdd-eb0c1a62fdaf

lib/OpenLayers/Popup.js

@@ -103,6 +103,17 @@ OpenLayers.Popup.prototype = {
         return this.div;
     },
 
+    /** 
+     * if the popup has a lonlat and its map members set, 
+     *  then have it move itself to its proper position
+     */
+    updatePosition: function() {
+        if ((this.lonlat) && (this.map)) {
+                px = this.map.getLayerPxFromLonLat(this.lonlat);
+                this.moveTo(px);            
+        }
+    },
+
     /**
     * @param {OpenLayers.Pixel} px
     */