LibGUI: Add a cancel button callback to settings window tabs

Some settings tabs, like the ones on the upcoming terminal settings,
need to know when the cancel button is pressed to clean up things like
temporary live updates. Therefore, the SettingsWindow::Tab now features
a cancel_settings callback which does not need to be implemented.

1 files changed, 2 insertions, 1 deletions

diff --git a/Userland/Libraries/LibGUI/SettingsWindow.h b/Userland/Libraries/LibGUI/SettingsWindow.h
index 96e897ac2c..f68d0922c7 100644
--- a/Userland/Libraries/LibGUI/SettingsWindow.h
+++ b/Userland/Libraries/LibGUI/SettingsWindow.h
@@ -20,7 +20,8 @@ public:
     class Tab : public GUI::Widget {
     public:
         virtual void apply_settings() = 0;
-        virtual void reset_default_values() {};
+        virtual void cancel_settings() { }
+        virtual void reset_default_values() { }
     };
 
     enum class ShowDefaultsButton {