[gimp] app: don't leak the identifier if gimp_data_make_internal() is called again

[Michael Natterer <mitch src gnome org>]

commit f23958407ccecaadb4c5186d7ac051ad8be66633
Author: Michael Natterer <mitch gimp org>
Date:   Sun Jun 3 22:43:55 2018 +0200

    app: don't leak the identifier if gimp_data_make_internal() is called again

 app/core/gimpdata.c | 8 +++++---
 1 file changed, 5 insertions(+), 3 deletions(-)
---
diff --git a/app/core/gimpdata.c b/app/core/gimpdata.c
index 4a58f368e1..a6cf92c8ed 100644
--- a/app/core/gimpdata.c
+++ b/app/core/gimpdata.c
@@ -1217,10 +1217,12 @@ gimp_data_make_internal (GimpData    *data,
 
   g_clear_object (&private->file);
 
+  g_free (private->identifier);
   private->identifier = g_strdup (identifier);
-  private->writable   = FALSE;
-  private->deletable  = FALSE;
-  private->internal   = TRUE;
+
+  private->writable  = FALSE;
+  private->deletable = FALSE;
+  private->internal  = TRUE;
 }
 
 gboolean