[gimp/metadata-browser] app: don't detach the floating selection if it's not attached

[Roman Joost <romanofski src gnome org>]

commit f0f80736c31f69d0147842dffc6161e52a4e599f
Author: Michael Natterer <mitch gimp org>
Date:   Fri Sep 23 22:24:23 2011 +0200

    app: don't detach the floating selection if it's not attached
    
    Fix the commit two down in the log: a layer can be a floating
    selection even if it's not attached to anything (when it is on the
    undo stack).  Don't detach it if it is not the underlying drawable's
    current fs.

 app/core/gimplayer.c |    6 +++++-
 1 files changed, 5 insertions(+), 1 deletions(-)
---
diff --git a/app/core/gimplayer.c b/app/core/gimplayer.c
index 2771b88..5666d27 100644
--- a/app/core/gimplayer.c
+++ b/app/core/gimplayer.c
@@ -406,7 +406,11 @@ gimp_layer_dispose (GObject *object)
     {
       GimpDrawable *fs_drawable = gimp_layer_get_floating_sel_drawable (layer);
 
-      gimp_drawable_detach_floating_sel (fs_drawable);
+      /* only detach if this is actually the drawable's fs because the
+       * layer might be on the undo stack and not attached to anyhing
+       */
+      if (gimp_drawable_get_floating_sel (fs_drawable) == layer)
+        gimp_drawable_detach_floating_sel (fs_drawable);
     }
 
   G_OBJECT_CLASS (parent_class)->dispose (object);