GUI2/Window: removed now-unused members

Neither of these are necessary with the accelerated rendering drawing refactor of GUI2.

src/gui/widgets/window.cpp

@@ -280,7 +280,6 @@ window::window(CVideo& video,
 	, variables_()
 	, invalidate_layout_blocked_(false)
 	, suspend_drawing_(true)
-	, is_toplevel_(!is_in_dialog())
 	, automatic_placement_(automatic_placement)
 	, horizontal_placement_(horizontal_placement)
 	, vertical_placement_(vertical_placement)
@@ -299,7 +298,6 @@ window::window(CVideo& video,
 	, escape_disabled_(false)
 	, linked_size_()
 	, mouse_button_state_(0) /**< Needs to be initialized in @ref show. */
-	, dirty_list_()
 #ifdef DEBUG_WINDOW_LAYOUT_GRAPHS
 	, debug_layout_(new debug_layout_graph(this))
 #endif

src/gui/widgets/window.hpp

@@ -199,17 +199,6 @@ class window : public panel, public cursor::setter
 	 */
 	void draw();
 
-	/**
-	 * Adds an item to the dirty_list_.
-	 *
-	 * @param call_stack          The list of widgets traversed to get to the
-	 *                            dirty widget.
-	 */
-	void add_to_dirty_list(const std::vector<widget*>& call_stack)
-	{
-		dirty_list_.push_back(call_stack);
-	}
-
 	/** The status of the window. */
 	enum status {
 		NEW,		   /**< The window is new and not yet shown. */
@@ -541,9 +530,6 @@ class window : public panel, public cursor::setter
 	/** Avoid drawing the window.  */
 	bool suspend_drawing_;
 
-	/** Whether the window has other windows behind it */
-	bool is_toplevel_;
-
 	/** Do we wish to place the widget automatically? */
 	const bool automatic_placement_;
 
@@ -698,14 +684,6 @@ class window : public panel, public cursor::setter
 	/** See @ref styled_widget::get_control_type. */
 	virtual const std::string& get_control_type() const override;
 
-	/**
-	 * The list with dirty items in the window.
-	 *
-	 * When drawing only the widgets that are dirty are updated. The draw()
-	 * function has more information about the dirty_list_.
-	 */
-	std::vector<std::vector<widget*> > dirty_list_;
-
 	/**
 	 * Finishes the initialization of the grid.
 	 *