Limit link picker to content tree in content section (#12311)

* Remove unused injected mediaHelper

* Limit tree to content tree alias in content section

src/Umbraco.Web.UI.Client/src/views/common/infiniteeditors/linkpicker/linkpicker.controller.js

@@ -1,6 +1,6 @@
 //used for the media picker dialog
 angular.module("umbraco").controller("Umbraco.Editors.LinkPickerController",
-    function ($scope, eventsService, entityResource, mediaResource, mediaHelper, udiParser, userService, localizationService, editorService) {
+    function ($scope, eventsService, entityResource, mediaResource, udiParser, userService, localizationService, editorService) {
 
         var vm = this;
         var dialogOptions = $scope.model;
@@ -20,6 +20,7 @@ angular.module("umbraco").controller("Umbraco.Editors.LinkPickerController",
                     $scope.model.title = value;
                 });
         }
+        
         $scope.customTreeParams = dialogOptions.dataTypeKey ? "dataTypeKey=" + dialogOptions.dataTypeKey : "";
         $scope.dialogTreeApi = {};
         $scope.model.target = {};

src/Umbraco.Web.UI.Client/src/views/common/infiniteeditors/linkpicker/linkpicker.html

@@ -85,6 +85,7 @@
 
                             <div ng-hide="searchInfo.showSearch">
                                 <umb-tree section="content"
+                                          treealias="content"
                                           hideheader="true"
                                           hideoptions="true"
                                           api="dialogTreeApi"