[gtkmm] Update some documentation.

[Murray Cumming <murrayc src gnome org>]

commit 75fe0edec434d073c8fe652aa1aed9361ad9ef37
Author: Murray Cumming <murrayc murrayc com>
Date:   Wed Oct 9 10:28:11 2013 +0200

    Update some documentation.

 gdk/src/window.hg       |    6 +++++-
 gtk/src/cellrenderer.hg |    5 -----
 2 files changed, 5 insertions(+), 6 deletions(-)
---
diff --git a/gdk/src/window.hg b/gdk/src/window.hg
index b365afb..5096c8f 100644
--- a/gdk/src/window.hg
+++ b/gdk/src/window.hg
@@ -266,7 +266,11 @@ public:
   _WRAP_METHOD_DOCS_ONLY(gdk_window_get_drag_protocol)
   DragProtocol get_drag_protocol(Glib::RefPtr<Window>& target) const;
 
-  //TODO: Documentation
+  /** Finds out the DND protocol supported by a window.
+   * 
+   * @newin{3,0}
+   * @return The supported DND protocol.
+   */
   DragProtocol get_drag_protocol() const;
 
   _IGNORE(gdk_window_get_drag_protocol)
diff --git a/gtk/src/cellrenderer.hg b/gtk/src/cellrenderer.hg
index 9d55dc8..80c0ff2 100644
--- a/gtk/src/cellrenderer.hg
+++ b/gtk/src/cellrenderer.hg
@@ -121,11 +121,6 @@ public:
 
 #m4 _CONVERSION(`const char*',`const Glib::ustring&',__GCHARP_TO_USTRING)
 
-  //TODO: Remove the warning in the documentation when we have fixed the
-  //inheritance of CellRendererCombo.
-  /** Note that this signal does not work yet in gtkmm.
-   * See http://bugzilla.gnome.org/show_bug.cgi?id=301597
-   */
   _WRAP_SIGNAL(void editing_started(CellEditable* editable, const Glib::ustring& path), editing_started)
 
   _WRAP_PROPERTY("mode", CellRendererMode)