xdg-shell: Rename set_transient_for to set_parent

It's a confusing name that comes from the ICCCM. The ICCCM is best
forgotten about.

With the addition of the potential new "transient" role meaning a
parent-relative toplevel like a long-lived popup, used for e.g.
tooltips, the set_transient_for name will become even more confusing.

clients/stacking.c

@@ -64,7 +64,7 @@ new_window(struct stacking *stacking, struct window *parent_window)
 	struct widget *new_widget;
 
 	new_window = window_create(stacking->display);
-	window_set_transient_for(new_window, parent_window);
+	window_set_parent(new_window, parent_window);
 
 	new_widget = window_frame_create(new_window, new_window);
 
@@ -230,7 +230,7 @@ draw_string(cairo_t *cr,
 static void
 set_window_background_colour(cairo_t *cr, struct window *window)
 {
-	if (window_get_transient_for(window))
+	if (window_get_parent(window))
 		cairo_set_source_rgba(cr, 0.0, 1.0, 0.0, 0.4);
 	else if (window_is_maximized(window))
 		cairo_set_source_rgba(cr, 1.0, 1.0, 0.0, 0.6);
@@ -276,7 +276,7 @@ redraw_handler(struct widget *widget, void *data)
 	            "      (n)ew window, (p)opup,\n"
 	            "      (q)uit, (t)ransient window\n",
 	            window, window_is_fullscreen(window),
-	            window_is_maximized(window), window_get_transient_for(window) ? 1 : 0);
+	            window_is_maximized(window), window_get_parent(window) ? 1 : 0);
 
 	cairo_destroy(cr);
 }

clients/window.c

@@ -244,7 +244,7 @@ struct window {
 	struct xdg_surface *xdg_surface;
 	struct xdg_popup *xdg_popup;
 
-	struct window *transient_for;
+	struct window *parent;
 
 	struct window_frame *frame;
 
@@ -3912,19 +3912,19 @@ static const struct xdg_surface_listener xdg_surface_listener = {
 };
 
 static void
-window_sync_transient_for(struct window *window)
+window_sync_parent(struct window *window)
 {
 	struct wl_surface *parent_surface;
 
 	if (!window->xdg_surface)
 		return;
 
-	if (window->transient_for)
-		parent_surface = window->transient_for->main_surface->surface;
+	if (window->parent)
+		parent_surface = window->parent->main_surface->surface;
 	else
 		parent_surface = NULL;
 
-	xdg_surface_set_transient_for(window->xdg_surface, parent_surface);
+	xdg_surface_set_parent(window->xdg_surface, parent_surface);
 }
 
 static void
@@ -3955,7 +3955,7 @@ window_flush(struct window *window)
 
 	if (!window->custom) {
 		if (window->xdg_surface) {
-			window_sync_transient_for(window);
+			window_sync_parent(window);
 			window_sync_margin(window);
 		}
 	}
@@ -4428,17 +4428,17 @@ window_create_custom(struct display *display)
 }
 
 void
-window_set_transient_for(struct window *window,
+window_set_parent(struct window *window,
 		  struct window *parent_window)
 {
-	window->transient_for = parent_window;
-	window_sync_transient_for(window);
+	window->parent = parent_window;
+	window_sync_parent(window);
 }
 
 struct window *
-window_get_transient_for(struct window *window)
+window_get_parent(struct window *window)
 {
-	return window->transient_for;
+	return window->parent;
 }
 
 static void

clients/window.h

@@ -275,9 +275,9 @@ struct window *
 window_create_custom(struct display *display);
 
 void
-window_set_transient_for(struct window *window, struct window *parent_window);
+window_set_parent(struct window *window, struct window *parent_window);
 struct window *
-window_get_transient_for(struct window *window);
+window_get_parent(struct window *window);
 
 int
 window_has_focus(struct window *window);

desktop-shell/shell.c

@@ -3354,7 +3354,7 @@ xdg_surface_destroy(struct wl_client *client,
 }
 
 static void
-xdg_surface_set_transient_for(struct wl_client *client,
+xdg_surface_set_parent(struct wl_client *client,
 		       struct wl_resource *resource,
 		       struct wl_resource *parent_resource)
 {
@@ -3515,7 +3515,7 @@ xdg_surface_set_minimized(struct wl_client *client,
 
 static const struct xdg_surface_interface xdg_surface_implementation = {
 	xdg_surface_destroy,
-	xdg_surface_set_transient_for,
+	xdg_surface_set_parent,
 	xdg_surface_set_margin,
 	xdg_surface_set_title,
 	xdg_surface_set_app_id,

protocol/xdg-shell.xml

@@ -137,11 +137,8 @@
       </description>
     </request>
 
-    <request name="set_transient_for">
+    <request name="set_parent">
       <description summary="surface is a child of another surface">
-	Setting a surface as transient of another means that it is child
-	of another surface.
-
 	Child surfaces are stacked above their parents, and will be
 	unmapped if the parent is unmapped too. They should not appear
 	on task bars and alt+tab.