[gtkmm] Fix the build with the latest GTK+.

[Murray Cumming <murrayc src gnome org>]

commit 3ba9131c341e9153dee2a937f061472feb225a8f
Author: Murray Cumming <murrayc murrayc com>
Date:   Fri Nov 26 13:43:28 2010 +0100

    Fix the build with the latest GTK+.
    
    * gtk/gtkmm/targetentry.cc: Destructor: Use const_cast<> so we can
    g_free() our dynamically-allocated GtkTargetEntry::target string.
    The const change in GTK+ does not seem wise:
    https://bugzilla.gnome.org/show_bug.cgi?id=565665#c10

 ChangeLog                |    9 +++++++++
 gtk/gtkmm/targetentry.cc |    4 +++-
 2 files changed, 12 insertions(+), 1 deletions(-)
---
diff --git a/ChangeLog b/ChangeLog
index fc00138..62678a9 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,5 +1,14 @@
 2010-11-26  Murray Cumming  <murrayc murrayc com>
 
+	Fix the build with the latest GTK+.
+
+	* gtk/gtkmm/targetentry.cc: Destructor: Use const_cast<> so we can 
+	g_free() our dynamically-allocated GtkTargetEntry::target string.
+	The const change in GTK+ does not seem wise:
+	https://bugzilla.gnome.org/show_bug.cgi?id=565665#c10
+
+2010-11-26  Murray Cumming  <murrayc murrayc com>
+
 	Ruler: Removed because it was removed from GTK+.
 
 	* gtk/src/ruler.[hg|ccg]: Removed.
diff --git a/gtk/gtkmm/targetentry.cc b/gtk/gtkmm/targetentry.cc
index fc646e9..037acfa 100644
--- a/gtk/gtkmm/targetentry.cc
+++ b/gtk/gtkmm/targetentry.cc
@@ -56,7 +56,9 @@ TargetEntry::TargetEntry(const TargetEntry& src)
 
 TargetEntry::~TargetEntry()
 {
-  g_free(gobject_.target);
+  //See https://bugzilla.gnome.org/show_bug.cgi?id=565665#c10 about the 
+  //const_cast<>.
+  g_free(const_cast<char*>(gobject_.target));
 }
 
 TargetEntry& TargetEntry::operator=(const TargetEntry& src)