diff --git a/gdk/gdk-private.h b/gdk/gdk-private.h
index 5b0955e5b8..1100087775 100644
--- a/gdk/gdk-private.h
+++ b/gdk/gdk-private.h
@@ -32,10 +32,6 @@ PangoDirection gdk_unichar_direction (gunichar    ch) G_GNUC_CONST;
 PangoDirection gdk_find_base_dir     (const char *text,
                                       int         len);
 
-void           gdk_surface_set_widget (GdkSurface *surface,
-                                       gpointer    widget);
-gpointer       gdk_surface_get_widget (GdkSurface *surface);
-
 typedef struct
 {
   const char *key;
diff --git a/gdk/gdksurface.c b/gdk/gdksurface.c
index 53c98c9158..82cb6ecf2f 100644
--- a/gdk/gdksurface.c
+++ b/gdk/gdksurface.c
@@ -46,8 +46,6 @@
 
 #include <math.h>
 
-#include <epoxy/gl.h>
-
 /**
  * GdkSurface:
  *
@@ -62,6 +60,13 @@
  * types exist, but you will rarely interact with them directly.
  */
 
+typedef struct _GdkSurfacePrivate GdkSurfacePrivate;
+
+struct _GdkSurfacePrivate
+{
+  gpointer widget;
+};
+
 enum {
   LAYOUT,
   RENDER,
@@ -109,7 +114,7 @@ static void gdk_surface_queue_set_is_mapped (GdkSurface *surface,
 static guint signals[LAST_SIGNAL] = { 0 };
 static GParamSpec *properties[LAST_PROP] = { NULL, };
 
-G_DEFINE_ABSTRACT_TYPE (GdkSurface, gdk_surface, G_TYPE_OBJECT)
+G_DEFINE_ABSTRACT_TYPE_WITH_PRIVATE (GdkSurface, gdk_surface, G_TYPE_OBJECT)
 
 static gboolean
 gdk_surface_real_beep (GdkSurface *surface)
@@ -994,16 +999,20 @@ gdk_surface_destroy (GdkSurface *surface)
 }
 
 void
-gdk_surface_set_widget (GdkSurface *surface,
+gdk_surface_set_widget (GdkSurface *self,
                         gpointer    widget)
 {
-  surface->widget = widget;
+  GdkSurfacePrivate *priv = gdk_surface_get_instance_private (self);
+
+  priv->widget = widget;
 }
 
 gpointer
-gdk_surface_get_widget (GdkSurface *surface)
+gdk_surface_get_widget (GdkSurface *self)
 {
-  return surface->widget;
+  GdkSurfacePrivate *priv = gdk_surface_get_instance_private (self);
+
+  return priv->widget;
 }
 
 /**
diff --git a/gdk/gdksurfaceprivate.h b/gdk/gdksurfaceprivate.h
index 3ab692e19c..16a6bf8bea 100644
--- a/gdk/gdksurfaceprivate.h
+++ b/gdk/gdksurfaceprivate.h
@@ -48,8 +48,6 @@ struct _GdkSurface
   gboolean pending_is_mapped;
   gboolean is_mapped;
 
-  gpointer widget;
-
   int x;
   int y;
 
@@ -294,8 +292,12 @@ void gdk_surface_get_geometry (GdkSurface *surface,
                                int        *width,
                                int        *height);
 
-void       gdk_surface_freeze_updates      (GdkSurface    *surface);
-void       gdk_surface_thaw_updates        (GdkSurface    *surface);
+void                    gdk_surface_set_widget                  (GdkSurface             *self,
+                                                                 gpointer                widget);
+gpointer                gdk_surface_get_widget                  (GdkSurface             *self);
+
+void                    gdk_surface_freeze_updates              (GdkSurface             *surface);
+void                    gdk_surface_thaw_updates                (GdkSurface             *surface);
 
 
 typedef enum
diff --git a/gtk/gtkdragicon.c b/gtk/gtkdragicon.c
index a58cf474dc..43c8940e03 100644
--- a/gtk/gtkdragicon.c
+++ b/gtk/gtkdragicon.c
@@ -19,7 +19,6 @@
 
 #include "gtkdragicon.h"
 
-#include "gtkprivate.h"
 #include "gtkintl.h"
 #include "gtkwidgetprivate.h"
 #include "gtkcssstyleprivate.h"
@@ -29,6 +28,8 @@
 #include "gtkcssboxesimplprivate.h"
 #include "gtkcssnumbervalueprivate.h"
 
+#include "gdk/gdksurfaceprivate.h"
+
 /* for the drag icons */
 #include "gtkcolorswatchprivate.h"
 #include "gtkimage.h"
diff --git a/gtk/gtknative.c b/gtk/gtknative.c
index 7856d4f486..8a0b74a062 100644
--- a/gtk/gtknative.c
+++ b/gtk/gtknative.c
@@ -21,11 +21,11 @@
 
 #include "gtknativeprivate.h"
 #include "gtkwidgetprivate.h"
-#include "gdk/gdk-private.h"
-#include "gtkprivate.h"
 #include "gtkintl.h"
 #include "gtkcssnodeprivate.h"
 
+#include "gdk/gdksurfaceprivate.h"
+
 typedef struct _GtkNativePrivate
 {
   gulong update_handler_id;
diff --git a/gtk/gtktexthandle.c b/gtk/gtktexthandle.c
index 0f92fc74d1..05f6d809aa 100644
--- a/gtk/gtktexthandle.c
+++ b/gtk/gtktexthandle.c
@@ -17,21 +17,22 @@
 
 #include "config.h"
 
-#include "gtkbinlayout.h"
-#include "gtkgizmoprivate.h"
-#include "gtkprivatetypebuiltins.h"
 #include "gtktexthandleprivate.h"
-#include "gtkmarshalers.h"
-#include "gtkprivate.h"
-#include "gtkwindowprivate.h"
-#include "gtkwidgetprivate.h"
-#include "gtkrendericonprivate.h"
+
+#include "gtkbinlayout.h"
 #include "gtkcssboxesimplprivate.h"
 #include "gtkcssnodeprivate.h"
-#include "gtknativeprivate.h"
+#include "gtkgesturedrag.h"
+#include "gtkgizmoprivate.h"
 #include "gtkintl.h"
+#include "gtkmarshalers.h"
+#include "gtknativeprivate.h"
+#include "gtkprivatetypebuiltins.h"
+#include "gtkrendericonprivate.h"
+#include "gtkwidgetprivate.h"
+#include "gtkwindowprivate.h"
 
-#include <gtk/gtk.h>
+#include "gdk/gdksurfaceprivate.h"
 
 enum {
   DRAG_STARTED,
diff --git a/gtk/gtktooltipwindow.c b/gtk/gtktooltipwindow.c
index a3dbf83db4..d316171600 100644
--- a/gtk/gtktooltipwindow.c
+++ b/gtk/gtktooltipwindow.c
@@ -26,13 +26,11 @@
 
 #include "gtktooltipwindowprivate.h"
 
-#include "gtkprivate.h"
-#include "gtkintl.h"
-
 #include "gtkbox.h"
 #include "gtkimage.h"
+#include "gtkintl.h"
 #include "gtklabel.h"
-#include "gtkmain.h"
+#include "gtkprivate.h"
 #include "gtksettings.h"
 #include "gtksizerequest.h"
 #include "gtkwindowprivate.h"
@@ -40,6 +38,8 @@
 #include "gtknativeprivate.h"
 #include "gtkcssboxesimplprivate.h"
 
+#include "gdk/gdksurfaceprivate.h"
+
 struct _GtkTooltipWindow
 {
   GtkWidget parent_instance;