[gimp] app: don't try to hide a NULL transform dialog

[Michael Natterer <mitch src gnome org>]

commit 1fa6497922b0d20cd06f8b261b211395534d8c65
Author: Michael Natterer <mitch gimp org>
Date:   Wed Feb 17 09:52:15 2010 +0100

    app: don't try to hide a NULL transform dialog

 app/tools/gimptransformtool.c |    3 ++-
 1 files changed, 2 insertions(+), 1 deletions(-)
---
diff --git a/app/tools/gimptransformtool.c b/app/tools/gimptransformtool.c
index 3c61d78..14a3b9b 100644
--- a/app/tools/gimptransformtool.c
+++ b/app/tools/gimptransformtool.c
@@ -1221,7 +1221,8 @@ gimp_transform_tool_doit (GimpTransformTool *tr_tool,
       return;
     }
 
-  gimp_dialog_factory_hide_dialog (tr_tool->dialog);
+  if (tr_tool->dialog)
+    gimp_dialog_factory_hide_dialog (tr_tool->dialog);
 
   mask_empty = gimp_channel_is_empty (gimp_image_get_mask (image));