gui2/toggle_button: Add a checkbox variation without a label

data/gui/widget/toggle_button_no_label.cfg

@@ -0,0 +1,112 @@
+#textdomain wesnoth-lib
+###
+### Definition of a toggle button without a label.
+###
+
+#define _GUI_RESOLUTION RESOLUTION WIDTH HEIGHT
+	[resolution]
+
+		{RESOLUTION}
+
+		min_width = {WIDTH}
+		min_height = {HEIGHT}
+
+		default_width = {WIDTH}
+		default_height = {HEIGHT}
+
+		max_width = 0
+		max_height = {HEIGHT}
+
+		[state]
+			[enabled]
+
+				[draw]
+
+					[image]
+						name = "buttons/checkbox.png"
+					[/image]
+
+				[/draw]
+
+			[/enabled]
+
+			[disabled]
+
+				[draw]
+
+					[image]
+						name = "buttons/checkbox.png~GS()"
+					[/image]
+
+				[/draw]
+
+			[/disabled]
+
+			[focused]
+
+				[draw]
+
+					[image]
+						name = "buttons/checkbox-active.png"
+					[/image]
+
+				[/draw]
+
+			[/focused]
+		[/state]
+
+		###
+		### Selected
+		###
+
+		[state]
+			[enabled]
+
+				[draw]
+
+					[image]
+						name = "buttons/checkbox-pressed.png"
+					[/image]
+
+				[/draw]
+
+			[/enabled]
+
+			[disabled]
+
+				[draw]
+
+					[image]
+						name = "buttons/checkbox-pressed.png~GS()"
+					[/image]
+
+				[/draw]
+
+			[/disabled]
+
+			[focused]
+
+				[draw]
+
+					[image]
+						name = "buttons/checkbox-active-pressed.png"
+					[/image]
+
+				[/draw]
+
+			[/focused]
+		[/state]
+
+	[/resolution]
+#enddef
+
+[toggle_button_definition]
+
+	id = "no_label"
+	description = "Checkbox without a label."
+
+	{_GUI_RESOLUTION () 20 18}
+
+[/toggle_button_definition]
+
+#undef _GUI_RESOLUTION