[meld] sourceview: Fix text-wrapping reset from commit dialog (bgo#741620)

[Kai Willadsen <kaiw src gnome org>]

commit f98a8da886ac1174d8c6d4a7b76faf2c50eccda5
Author: Kai Willadsen <kai willadsen gmail com>
Date:   Tue Dec 23 06:11:24 2014 +1000

    sourceview: Fix text-wrapping reset from commit dialog (bgo#741620)
    
    Because we set the wrap-mode forcefully in the commit dialog's
    sourceview, the gsettings binding was overriding the actual set
    preference.

 data/ui/vcview.ui  |    2 +-
 meld/sourceview.py |   11 +++++++++++
 2 files changed, 12 insertions(+), 1 deletions(-)
---
diff --git a/data/ui/vcview.ui b/data/ui/vcview.ui
index be13b84..d63e362 100644
--- a/data/ui/vcview.ui
+++ b/data/ui/vcview.ui
@@ -277,7 +277,7 @@
                             <property name="can_focus">True</property>
                             <property name="shadow_type">in</property>
                             <child>
-                              <object class="MeldSourceView" id="textview">
+                              <object class="CommitMessageSourceView" id="textview">
                                 <property name="visible">True</property>
                                 <property name="can_focus">True</property>
                                 <property name="wrap_mode">word</property>
diff --git a/meld/sourceview.py b/meld/sourceview.py
index 97bc65b..1e2edc6 100644
--- a/meld/sourceview.py
+++ b/meld/sourceview.py
@@ -96,3 +96,14 @@ class MeldSourceView(GtkSource.View):
 
     def get_line_num_for_y(self, y):
         return self.get_line_at_y(y)[0].get_line()
+
+
+class CommitMessageSourceView(GtkSource.View):
+
+    __gtype_name__ = "CommitMessageSourceView"
+
+    __gsettings_bindings__ = (
+        ('indent-width', 'tab-width'),
+        ('insert-spaces-instead-of-tabs', 'insert-spaces-instead-of-tabs'),
+        ('draw-spaces', 'draw-spaces'),
+    )