xim: Stop using gdk_surface_get_user_data

Use gtk_root_get_for_surface instead.

gtk/gtkimcontextime.c

@@ -29,6 +29,7 @@
 
 #include "gtkimcontextime.h"
 #include "gtkimmoduleprivate.h"
+#include "gtkroot.h"
 
 #include "imm-extra.h"
 
@@ -878,9 +879,9 @@ gtk_im_context_ime_set_preedit_font (GtkIMContext *context)
   if (!context_ime->client_surface)
     return;
 
-  gdk_surface_get_user_data (context_ime->client_surface, (gpointer) &widget);
-  if (!GTK_IS_WIDGET (widget))
-    return;
+  widget = gtk_root_get_for_surface (context_ime->client_surface);
+  if (!widget)
+    return
 
   hwnd = gdk_win32_surface_get_impl_hwnd (context_ime->client_surface);
   himc = ImmGetContext (hwnd);

gtk/gtkimcontextxim.c

@@ -22,6 +22,7 @@
 
 #include "gtkimcontextxim.h"
 #include "gtkimmoduleprivate.h"
+#include "gtkroot.h"
 
 #include "gtk/gtkintl.h"
 
@@ -1526,32 +1527,13 @@ on_client_widget_hierarchy_changed (GtkWidget       *widget,
   update_in_toplevel (context_xim);
 }
 
-/* Finds the GtkWidget that owns the window, or if none, the
- * widget owning the nearest parent that has a widget.
- */
-static GtkWidget *
-widget_for_window (GdkSurface *window)
-{
-  while (window)
-    {
-      gpointer user_data;
-      gdk_surface_get_user_data (window, &user_data);
-      if (user_data)
-	return user_data;
-
-      window = gdk_surface_get_parent (window);
-    }
-
-  return NULL;
-}
-
 /* Called when context_xim->client_surface changes; takes care of
  * removing and/or setting up our watches for the toplevel
  */
 static void
 update_client_widget (GtkIMContextXIM *context_xim)
 {
-  GtkWidget *new_client_widget = widget_for_window (context_xim->client_surface);
+  GtkWidget *new_client_widget = gtk_root_get_for_surface (context_xim->client_surface);
 
   if (new_client_widget != context_xim->client_widget)
     {

gtk/gtkroot.c

@@ -102,3 +102,24 @@ gtk_root_get_surface_transform (GtkRoot *self,
   iface = GTK_ROOT_GET_IFACE (self);
   return iface->get_surface_transform (self, x, y);
 }
+
+/**
+ * gtk_root_get_for_surface:
+ * @surface: a #GdkSurface
+ *
+ * Finds the GtkRoot associated with the surface.
+ * 
+ * Returns: (transfer none): the #GtkRoot that is associated with @surface
+ */
+GtkWidget *
+gtk_root_get_for_surface (GdkSurface *surface)
+{
+  gpointer user_data;
+
+  gdk_surface_get_user_data (surface, &user_data);
+
+  if (user_data && GTK_IS_ROOT (user_data))
+    return GTK_WIDGET (user_data);
+
+  return NULL;
+}

gtk/gtkroot.h

@@ -53,6 +53,8 @@ struct _GtkRootInterface
                                                          int                    *y);
 };
 
+GDK_AVAILABLE_IN_ALL
+GtkWidget * gtk_root_get_for_surface (GdkSurface *surface);
 
 G_END_DECLS