[glade] Reverting change from notebook-actions branch merge.

[Tristan Van Berkom <tvb src gnome org>]

commit aaebdb3daa71962bd209a054858e5f8a97f3d749
Author: Tristan Van Berkom <tristan upstairslabs com>
Date:   Mon Dec 14 15:25:15 2015 +0900

    Reverting change from notebook-actions branch merge.
    
    It seems Matthias was testing headerbars in dialogs as was
    suggested in the WONTFIX'ed bug 757562. Reverting the enabling
    of headerbars in dialogs.
    
    Also updated the comment in gtk+.xml.in around the headerbar
    disabling, originally it was because it was unsupported (yet),
    now it is because dialogs own their headerbars.

 plugins/gtk+/gtk+.xml.in |    4 ++--
 1 files changed, 2 insertions(+), 2 deletions(-)
---
diff --git a/plugins/gtk+/gtk+.xml.in b/plugins/gtk+/gtk+.xml.in
index 8a62168..c820b9b 100644
--- a/plugins/gtk+/gtk+.xml.in
+++ b/plugins/gtk+/gtk+.xml.in
@@ -2232,8 +2232,8 @@
           <property id="default-width"  default="320" optional="True" optional-default="False"/>
           <property id="default-height" default="260" optional="True" optional-default="False"/>
           <property id="type-hint" default="GDK_WINDOW_TYPE_HINT_DIALOG" save-always="True"/>
-          <!-- We disabled this property until Glade supports GtkHeaderBar editing -->
-          <property id="use-header-bar" since="3.12" disabled="False"/>
+          <!-- Dialogs have special automatic handling of the headerbar, they own the headerbar -->
+          <property id="use-header-bar" since="3.12" disabled="True"/>
         </properties>
         
       </glade-widget-class>