Fix FSAA dropdown option reset after changing another dropdown option

builtin/mainmenu/tab_settings.lua

@@ -109,8 +109,7 @@ local function antialiasing_fname_to_name(fname)
 			return antialiasing[2][i]
 		end
 	end
-
-   return "0"
+	return 0
 end
 
 local function dlg_confirm_reset_formspec(data)
@@ -418,8 +417,11 @@ local function handle_settings_buttons(this, fields, tabname, tabdata)
 		core.setting_set("anisotropic_filter", "true")
 		ddhandled = true
 	end
+	if fields["dd_antialiasing"] then
 		core.setting_set("fsaa",
 			antialiasing_fname_to_name(fields["dd_antialiasing"]))
+		ddhandled = true
+	end
 
 	return ddhandled
 end