updates when the tree does it's initialization , fixes migration

src/Umbraco.Web.UI.Client/src/common/directives/components/tree/umbtree.directive.js

@@ -53,7 +53,9 @@ function umbTreeDirective($compile, $log, $q, $rootScope, treeService, notificat
 
         controller: function ($scope, $element) {
 
-            var vm = this;
+            var vm = this;
+
+            var isInitialized = false;
 
             var registeredCallbacks = {
                 treeNodeExpanded: [],
@@ -269,9 +271,17 @@ function umbTreeDirective($compile, $log, $q, $rootScope, treeService, notificat
 
                     return treeService.getTree(args)
                         .then(function (data) {
+
                             //set the data once we have it
                             $scope.tree = data;
 
+                            //call the callback, this allows for hosting controllers to bind to events and use the exposed API
+                            if (!isInitialized) {
+                                isInitialized = true;
+                                $scope.onInit();
+                            }
+                            
+
                             enableDeleteAnimations();
 
                             $scope.loading = false;
@@ -421,9 +431,6 @@ function umbTreeDirective($compile, $log, $q, $rootScope, treeService, notificat
                     lastSection = newVal;
                 }
             });
-
-            //call the callback, this allows for hosting controllers to bind to events and use the exposed API
-            $scope.onInit();
             
             loadTree();
         }