drive-menu: Don't assume mounts without volume are local

The intention of the code is to only expose actually plugged in
devices rather than network mounts, but the existing heuristics are
based on GVolume and simply assume a local mount where there's no
associated volume. Fill that gap by querying the ::remote filesystem
attribute in that case.

https://gitlab.gnome.org/GNOME/gnome-shell-extensions/issues/53

Part-of: <https://gitlab.gnome.org/GNOME/gnome-shell-extensions/-/merge_requests/27>
(cherry picked from commit 7d6670ce3c)

extensions/drive-menu/extension.js

@@ -62,13 +62,21 @@ class MountMenuItem extends PopupMenu.PopupBaseMenuItem {
 
         let volume = this.mount.get_volume();
 
-        if (!volume) {
-            // probably a GDaemonMount, could be network or
-            // local, but we can't tell; assume it's local for now
-            return true;
+        if (volume)
+            return volume.get_identifier('class') !== 'network';
+
+        const root = this.mount.get_root();
+
+        try {
+            const attr = Gio.FILE_ATTRIBUTE_FILESYSTEM_REMOTE;
+            const info = root.query_filesystem_info(attr, null);
+            return !info.get_attribute_boolean(attr);
+        } catch (e) {
+            log(`Failed to query filesystem: ${e.message}`);
         }
 
-        return volume.get_identifier('class') !== 'network';
+        // Hack, fall back to looking at GType
+        return Gio._LocalFilePrototype.isPrototypeOf(root);
     }
 
     _syncVisibility() {