Browser: Make removal of bookmark persistent (#1865)

Json model wasn't stored after bookmark removal.
Store the model if remove() was successful.

Applications/Browser/BookmarksBarWidget.cpp

@@ -184,8 +184,12 @@ bool BookmarksBarWidget::remove_bookmark(const String& url)
         auto item_url = model()->data(model()->index(item_index, 1)).to_string();
         if (item_url == url) {
             auto& json_model = *static_cast<GUI::JsonArrayModel*>(model());
-            json_model.remove(item_index);
-            return true;
+
+            const auto item_removed = json_model.remove(item_index);
+            if (item_removed)
+                json_model.store();
+
+            return item_removed;
         }
     }