Media Picker Fixed folder navigation when returning from an empty folder (closes #20975) (#20987)

* Fixed media picker folder navigation when returning from an empty folder.

* Applied suggestions from code review.

Author: AndyButland

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

@@ -595,8 +595,13 @@ angular.module("umbraco")
 
             function syncPagination(opts, data) {
                 var d = data || {};
+                if (d.pageNumber > 0) {
+                    opts.pageNumber = d.pageNumber;
+                }
                 opts.pageNumber = d.pageNumber;
-                opts.pageSize   = d.pageSize;
+                if (d.pageSize > 0) {
+                    opts.pageSize = d.pageSize;
+                }
                 opts.totalItems = d.totalItems;
                 opts.totalPages = d.totalPages;
             }