[gnote] Use use use_client_side_decorations

[Aurimas Černius <aurimasc src gnome org>]

commit 346134a5059f072ee27c1de486444bd5ac6bc23a
Author: Aurimas Černius <aurisc4 gmail com>
Date:   Sat Dec 19 18:38:32 2020 +0200

    Use use use_client_side_decorations

 src/mainwindow.cpp | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)
---
diff --git a/src/mainwindow.cpp b/src/mainwindow.cpp
index 1e55f44e..bdd5ca9f 100644
--- a/src/mainwindow.cpp
+++ b/src/mainwindow.cpp
@@ -107,8 +107,7 @@ MainWindow *MainWindow::present_default(IGnote & g, const Note::Ptr & note)
 bool MainWindow::use_client_side_decorations(Preferences & prefs)
 {
   if(s_use_client_side_decorations < 0) {
-    Glib::ustring setting = prefs.get_schema_settings(Preferences::SCHEMA_GNOTE)->get_string(
-      Preferences::USE_CLIENT_SIDE_DECORATIONS);
+    auto setting = prefs.use_client_side_decorations();
     if(setting == "enabled") {
       s_use_client_side_decorations = 1;
     }