Fixes: U4-5011 Auto collapsing tree structure

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

@@ -132,8 +132,26 @@ function umbTreeDirective($compile, $log, $q, $rootScope, treeService, notificat
                             //reset current node selection
                             //scope.currentNode = null;
 
-                            //filter the path for root node ids
+                            //Filter the path for root node ids (we don't want to pass in -1 or 'init')
+
                             args.path = _.filter(args.path, function (item) { return (item !== "init" && item !== "-1"); });
+
+                            //Once those are filtered we need to check if the current user has a special start node id, 
+                            // if they do, then we're going to trim the start of the array for anything found from that start node
+                            // and previous so that the tree syncs properly. The tree syncs from the top down and if there are parts
+                            // of the tree's path in there that don't actually exist in the dom/model then syncing will not work.
+
+                            var startNodes = [Umbraco.Sys.ServerVariables.security.startContentId, Umbraco.Sys.ServerVariables.security.startMediaId];
+                            _.each(startNodes, function (i) {
+                                var found = _.find(args.path, function(p) {
+                                    return String(p) === String(i);
+                                });
+                                if (found) {
+                                    args.path = args.path.splice(_.indexOf(args.path, found));
+                                }
+                            });
+                            
+                            
                             loadPath(args.path, args.forceReload, args.activate);
 
                             return deferred.promise;

src/Umbraco.Web.UI.Client/src/common/mocks/umbraco.servervariables.js

@@ -33,6 +33,10 @@ Umbraco.Sys.ServerVariables = {
             { alias: "myTree", packageFolder: "MyPackage" }
         ]
     },
+    security : {
+        startContentId: -1,
+        startMediaId: -1
+    },
     isDebuggingEnabled: true,
     application: {
         assemblyVersion: "1",

src/Umbraco.Web/Editors/BackOfficeController.cs

@@ -235,6 +235,13 @@ namespace Umbraco.Web.Editors
                                 {"trees", GetTreePluginsMetaData()}
                             }
                     },
+                    {
+                        "security", new Dictionary<string, object>
+                            {
+                                {"startContentId", Security.CurrentUser.StartContentId},
+                                {"startMediaId", Security.CurrentUser.StartMediaId}
+                            }
+                    },
                     {"isDebuggingEnabled", HttpContext.IsDebuggingEnabled},
                     {
                         "application", GetApplicationState()