Remove Icon-specific code from Markers Layer, patch by meek,me,

r=euzuro.  (Closes #818)


git-svn-id: http://svn.openlayers.org/trunk/openlayers@9233 dc9f47b5-9b13-0410-9fdd-eb0c1a62fdaf

lib/OpenLayers/Marker.js

@@ -89,6 +89,9 @@ OpenLayers.Marker = OpenLayers.Class({
      * know which layer it is attached to.)
      */
     destroy: function() {
+        // erase any drawn features
+        this.erase();
+
         this.map = null;
 
         this.events.destroy();
@@ -115,6 +118,16 @@ OpenLayers.Marker = OpenLayers.Class({
         return this.icon.draw(px);
     }, 
 
+    /** 
+    * Method: erase
+    * Erases any drawn elements for this marker.
+    */
+    erase: function() {
+        if (this.icon != null) {
+            this.icon.erase();
+        }
+    }, 
+
     /**
     * Method: moveTo
     * Move the marker to the new location.