[gtk+] Add a message-dialog style class

[Matthias Clasen <matthiasc src gnome org>]

commit 9bc07a263474cd2092ec54c00b8a5d93244cf0a0
Author: Matthias Clasen <mclasen redhat com>
Date:   Thu Jun 12 09:14:03 2014 -0400

    Add a message-dialog style class
    
    This helps in separating message dialogs from other dialogs,
    theming-wise.

 docs/reference/gtk/gtk3-sections.txt |    1 +
 gtk/gtkstylecontext.h                |    9 +++++++++
 gtk/resources/ui/gtkmessagedialog.ui |    3 +++
 3 files changed, 13 insertions(+), 0 deletions(-)
---
diff --git a/docs/reference/gtk/gtk3-sections.txt b/docs/reference/gtk/gtk3-sections.txt
index 754eb8a..5896a79 100644
--- a/docs/reference/gtk/gtk3-sections.txt
+++ b/docs/reference/gtk/gtk3-sections.txt
@@ -5994,6 +5994,7 @@ GTK_STYLE_CLASS_MARK
 GTK_STYLE_CLASS_MENU
 GTK_STYLE_CLASS_MENUBAR
 GTK_STYLE_CLASS_MENUITEM
+GTK_STYLE_CLASS_MESSAGE_DIALOG
 GTK_STYLE_CLASS_NEEDS_ATTENTION
 GTK_STYLE_CLASS_NOTEBOOK
 GTK_STYLE_CLASS_OSD
diff --git a/gtk/gtkstylecontext.h b/gtk/gtkstylecontext.h
index 41607f5..6804616 100644
--- a/gtk/gtkstylecontext.h
+++ b/gtk/gtkstylecontext.h
@@ -808,6 +808,15 @@ struct _GtkStyleContextClass
 #define GTK_STYLE_CLASS_POPUP "popup"
 
 /**
+ * GTK_STYLE_CLASS_MESSAGE_DIALOG:
+ *
+ * A CSS class that is added to message dialogs.
+ *
+ * Since: 3.14
+ */
+#define GTK_STYLE_CLASS_MESSAGE_DIALOG "message-dialog"
+
+/**
  * GTK_STYLE_REGION_ROW:
  *
  * A widget region name to define a treeview row.
diff --git a/gtk/resources/ui/gtkmessagedialog.ui b/gtk/resources/ui/gtkmessagedialog.ui
index d75a414..78678f9 100644
--- a/gtk/resources/ui/gtkmessagedialog.ui
+++ b/gtk/resources/ui/gtkmessagedialog.ui
@@ -8,6 +8,9 @@
     <property name="resizable">False</property>
     <property name="type_hint">dialog</property>
     <property name="skip_taskbar_hint">True</property>
+    <style>
+      <class name="message-dialog"/>
+    </style>
     <child internal-child="headerbar">
       <object class="GtkHeaderBar" id="headerbar1">
         <property name="visible">True</property>