remoteSearch: exclude content from hidden apps

Some apps may be configured as NoDisplay=true, but still install
a search provider.
Like we do elsewhere, exclude them from showing up in the UI.

https://gitlab.gnome.org/GNOME/gnome-shell/merge_requests/568

js/ui/remoteSearch.js

@@ -89,6 +89,8 @@ function loadRemoteSearchProviders(searchSettings, callback) {
             try {
                 let desktopId = keyfile.get_string(group, 'DesktopId');
                 appInfo = Gio.DesktopAppInfo.new(desktopId);
+                if (!appInfo.should_show())
+                    return;
             } catch (e) {
                 log('Ignoring search provider ' + path + ': missing DesktopId');
                 return;