[gimp] Bug 769340 - GIF export dialog: false memory.

[Jehan Pagès <jehanp src gnome org>]

commit 99a22418b9203a24ba1dcf7aa48b3beb07a7a5ca
Author: Jehan <jehan girinstud io>
Date:   Sun Jul 31 06:23:43 2016 +0200

    Bug 769340 - GIF export dialog: false memory.
    
    "As animation" is checked while being insensitive on a single-layer
    image when previously exporting a GIF animation in the same session.

 plug-ins/common/file-gif-save.c |   18 +++++++++++-------
 1 files changed, 11 insertions(+), 7 deletions(-)
---
diff --git a/plug-ins/common/file-gif-save.c b/plug-ins/common/file-gif-save.c
index a708721..028f379 100644
--- a/plug-ins/common/file-gif-save.c
+++ b/plug-ins/common/file-gif-save.c
@@ -1311,14 +1311,18 @@ save_dialog (gint32 image_ID)
 
   frame  = GTK_WIDGET (gtk_builder_get_object (builder, "animation-frame"));
   toggle = GTK_WIDGET (gtk_builder_get_object (builder, "as-animation"));
-  gtk_widget_set_sensitive (toggle, animation_supported);
   if (! animation_supported)
-    gimp_help_set_help_data (toggle,
-                             _("You can only export as animation when the "
-                               "image has more than one layer. The image "
-                               "you are trying to export only has one "
-                               "layer."),
-                             NULL);
+    {
+      gimp_help_set_help_data (toggle,
+                               _("You can only export as animation when the "
+                                 "image has more than one layer. The image "
+                                 "you are trying to export only has one "
+                                 "layer."),
+                               NULL);
+      /* Make sure the checkbox is not checked from session data. */
+      gtk_toggle_button_set_active (GTK_TOGGLE_BUTTON (toggle), FALSE);
+    }
+  gtk_widget_set_sensitive (toggle, animation_supported);
 
   g_object_bind_property (toggle, "active",
                           frame,  "sensitive",