[clutter] gdk: Implement ClutterEventExtender

[Carlos Garnacho <carlosg src gnome org>]

commit a9b0715df1bc455567981b98a281b750efe64f29
Author: Carlos Garnacho <carlosg gnome org>
Date:   Tue Nov 17 19:44:38 2015 +0100

    gdk: Implement ClutterEventExtender
    
    This lifts the responsibility off its ClutterBackend.
    
    https://bugzilla.gnome.org/show_bug.cgi?id=758238

 clutter/gdk/clutter-backend-gdk.c        |   25 --------------------
 clutter/gdk/clutter-device-manager-gdk.c |   37 +++++++++++++++++++++++++++++-
 2 files changed, 36 insertions(+), 26 deletions(-)
---
diff --git a/clutter/gdk/clutter-backend-gdk.c b/clutter/gdk/clutter-backend-gdk.c
index ce5349d..d257c00 100644
--- a/clutter/gdk/clutter-backend-gdk.c
+++ b/clutter/gdk/clutter-backend-gdk.c
@@ -252,29 +252,6 @@ clutter_backend_gdk_get_features (ClutterBackend *backend)
         | CLUTTER_FEATURE_STAGE_CURSOR;
 }
 
-static void
-clutter_backend_gdk_copy_event_data (ClutterBackend     *backend,
-                                     const ClutterEvent *src,
-                                     ClutterEvent       *dest)
-{
-  GdkEvent *gdk_event;
-
-  gdk_event = _clutter_event_get_platform_data (src);
-  if (gdk_event != NULL)
-    _clutter_event_set_platform_data (dest, gdk_event_copy (gdk_event));
-}
-
-static void
-clutter_backend_gdk_free_event_data (ClutterBackend *backend,
-                                     ClutterEvent   *event)
-{
-  GdkEvent *gdk_event;
-
-  gdk_event = _clutter_event_get_platform_data (event);
-  if (gdk_event != NULL)
-    gdk_event_free (gdk_event);
-}
-
 static CoglRenderer *
 clutter_backend_gdk_get_renderer (ClutterBackend  *backend,
                                   GError         **error)
@@ -405,8 +382,6 @@ clutter_backend_gdk_class_init (ClutterBackendGdkClass *klass)
   backend_class->post_parse = _clutter_backend_gdk_post_parse;
 
   backend_class->get_features = clutter_backend_gdk_get_features;
-  backend_class->copy_event_data = clutter_backend_gdk_copy_event_data;
-  backend_class->free_event_data = clutter_backend_gdk_free_event_data;
 
   backend_class->get_renderer = clutter_backend_gdk_get_renderer;
   backend_class->get_display = clutter_backend_gdk_get_display;
diff --git a/clutter/gdk/clutter-device-manager-gdk.c b/clutter/gdk/clutter-device-manager-gdk.c
index 3442699..442aaa9 100644
--- a/clutter/gdk/clutter-device-manager-gdk.c
+++ b/clutter/gdk/clutter-device-manager-gdk.c
@@ -44,7 +44,12 @@
 
 #define clutter_device_manager_gdk_get_type     _clutter_device_manager_gdk_get_type
 
-G_DEFINE_TYPE (ClutterDeviceManagerGdk, clutter_device_manager_gdk, CLUTTER_TYPE_DEVICE_MANAGER)
+static void clutter_event_extender_iface_init   (ClutterEventExtenderInterface *iface);
+
+G_DEFINE_TYPE_WITH_CODE (ClutterDeviceManagerGdk, clutter_device_manager_gdk,
+                         CLUTTER_TYPE_DEVICE_MANAGER,
+                         G_IMPLEMENT_INTERFACE (CLUTTER_TYPE_EVENT_EXTENDER,
+                                                clutter_event_extender_iface_init))
 
 enum {
   PROP_0,
@@ -52,6 +57,36 @@ enum {
   PROP_LAST
 };
 
+static void
+clutter_device_manager_gdk_copy_event_data (ClutterEventExtender *event_extender,
+                                            const ClutterEvent   *src,
+                                            ClutterEvent         *dest)
+{
+  GdkEvent *gdk_event;
+
+  gdk_event = _clutter_event_get_platform_data (src);
+  if (gdk_event != NULL)
+    _clutter_event_set_platform_data (dest, gdk_event_copy (gdk_event));
+}
+
+static void
+clutter_device_manager_gdk_free_event_data (ClutterEventExtender *event_extender,
+                                            ClutterEvent         *event)
+{
+  GdkEvent *gdk_event;
+
+  gdk_event = _clutter_event_get_platform_data (event);
+  if (gdk_event != NULL)
+    gdk_event_free (gdk_event);
+}
+
+static void
+clutter_event_extender_iface_init (ClutterEventExtenderInterface *iface)
+{
+  iface->copy_event_data = clutter_device_manager_gdk_copy_event_data;
+  iface->free_event_data = clutter_device_manager_gdk_free_event_data;
+}
+
 ClutterInputDevice *
 _clutter_device_manager_gdk_lookup_device (ClutterDeviceManager *manager,
                                          GdkDevice            *device)