kinetic-scroll-view: Handle ClutterTimeline:stopped not :completed

The former is always emitted when the timeline stops (either due to
reaching its duration, or due to clutter_timeline_stop() being called);
the latter is only emitted in the first case.

Changing signals means we can eliminate manual cleanup code after calls
to clutter_timeline_stop().

clutter-project#98

mx/mx-kinetic-scroll-view.c

@@ -1087,17 +1087,17 @@ clamp_adjustments (MxKineticScrollView *scroll,
 }
 
 static void
-deceleration_completed_cb (ClutterTimeline     *timeline,
-                           MxKineticScrollView *scroll)
+deceleration_stopped_cb (ClutterTimeline     *timeline,
+                         gboolean             is_finished,
+                         MxKineticScrollView *scroll)
 {
   MxKineticScrollViewPrivate *priv = scroll->priv;
   guint duration;
 
   duration = (priv->overshoot > 0.0) ? priv->clamp_duration : 10;
   clamp_adjustments (scroll, duration, priv->hmoving, priv->vmoving);
 
-  g_object_unref (timeline);
-  priv->deceleration_timeline = NULL;
+  g_clear_object (&priv->deceleration_timeline);
 }
 
 static void
@@ -1201,7 +1201,6 @@ deceleration_new_frame_cb (ClutterTimeline     *timeline,
       if (stop)
         {
           clutter_timeline_stop (timeline);
-          deceleration_completed_cb (timeline, scroll);
         }
     }
 }
@@ -1464,8 +1463,8 @@ release_event (MxKineticScrollView *scroll,
 
               g_signal_connect (priv->deceleration_timeline, "new_frame",
                                 G_CALLBACK (deceleration_new_frame_cb), scroll);
-              g_signal_connect (priv->deceleration_timeline, "completed",
-                                G_CALLBACK (deceleration_completed_cb), scroll);
+              g_signal_connect (priv->deceleration_timeline, "stopped",
+                                G_CALLBACK (deceleration_stopped_cb), scroll);
               priv->accumulated_delta = 0;
               priv->hmoving = priv->vmoving = TRUE;
               clutter_timeline_start (priv->deceleration_timeline);
@@ -1530,9 +1529,6 @@ press_event (MxKineticScrollView *scroll,
           clutter_timeline_stop (priv->deceleration_timeline);
           g_object_unref (priv->deceleration_timeline);
           priv->deceleration_timeline = NULL;
-
-          clamp_adjustments (scroll, priv->clamp_duration, priv->hmoving,
-                             priv->vmoving);
         }
 
       if (priv->use_captured)