xwayland: Set decoration margin for xwayland windows

desktop-shell/shell.c

@@ -2052,6 +2052,16 @@ set_title(struct shell_surface *shsurf, const char *title)
 	shsurf->title = strdup(title);
 }
 
+static void
+set_margin(struct shell_surface *shsurf,
+	   int32_t left, int32_t right, int32_t top, int32_t bottom)
+{
+	shsurf->margin.left = left;
+	shsurf->margin.right = right;
+	shsurf->margin.top = top;
+	shsurf->margin.bottom = bottom;
+}
+
 static void
 shell_surface_set_title(struct wl_client *client,
 			struct wl_resource *resource, const char *title)
@@ -3349,10 +3359,7 @@ xdg_surface_set_margin(struct wl_client *client,
 {
 	struct shell_surface *shsurf = wl_resource_get_user_data(resource);
 
-	shsurf->margin.left = left;
-	shsurf->margin.right = right;
-	shsurf->margin.top = top;
-	shsurf->margin.bottom = bottom;
+	set_margin(shsurf, left, right, top, bottom);
 }
 
 static void
@@ -6112,6 +6119,7 @@ module_init(struct weston_compositor *ec,
 	ec->shell_interface.move = shell_interface_move;
 	ec->shell_interface.resize = surface_resize;
 	ec->shell_interface.set_title = set_title;
+	ec->shell_interface.set_margin = set_margin;
 
 	weston_layer_init(&shell->fullscreen_layer, &ec->cursor_layer.link);
 	weston_layer_init(&shell->panel_layer, &shell->fullscreen_layer.link);

src/compositor.h

@@ -111,7 +111,9 @@ struct weston_shell_interface {
 		      struct weston_seat *ws, uint32_t edges);
 	void (*set_title)(struct shell_surface *shsurf,
 	                  const char *title);
-
+	void (*set_margin)(struct shell_surface *shsurf,
+			   int32_t left, int32_t right,
+			   int32_t top, int32_t bottom);
 };
 
 struct weston_animation {

xwayland/window-manager.c

@@ -944,7 +944,8 @@ weston_wm_window_draw_decoration(void *data)
 	cairo_t *cr;
 	int x, y, width, height;
 	int32_t input_x, input_y, input_w, input_h;
-
+	struct weston_shell_interface *shell_interface =
+		&wm->server->compositor->shell_interface;
 	uint32_t flags = 0;
 
 	weston_wm_window_read_properties(window);
@@ -1006,6 +1007,12 @@ weston_wm_window_draw_decoration(void *data)
 
 		pixman_region32_init_rect(&window->surface->pending.input,
 					  input_x, input_y, input_w, input_h);
+		
+		shell_interface->set_margin(window->shsurf,
+					    input_x,
+					    width - input_w - input_x,
+					    input_y,
+					    height - input_h - input_y);
 	}
 }