if we destroy a popup, have it remove itself from the map. good programming says that a popup should be removed by the same person who added it... but if the user destroys a popup, s/he assumes it will dissapear, and unless we remove it, it wont do that.

git-svn-id: http://svn.openlayers.org/trunk/openlayers@538 dc9f47b5-9b13-0410-9fdd-eb0c1a62fdaf

lib/OpenLayers/Popup.js

@@ -75,6 +75,9 @@ OpenLayers.Popup.prototype = {
     /** 
     */
     destroy: function() {
+        if (this.map != null) {
+            this.map.removePopup(this);
+        }
         this.div = null;
         this.map = null;
     },