[gitg] Disconnect mapped signal in handler

[Jesse van den Kieboom <jessevdk src gnome org>]

commit d96671ddb5a602d0583a9623d96bbae37afb4e60
Author: Jesse van den Kieboom <jessevdk gnome org>
Date:   Wed Dec 30 18:26:23 2015 +0100

    Disconnect mapped signal in handler

 libgitg/gitg-when-mapped.vala |    1 +
 1 files changed, 1 insertions(+), 0 deletions(-)
---
diff --git a/libgitg/gitg-when-mapped.vala b/libgitg/gitg-when-mapped.vala
index fbb7d69..4142ab2 100644
--- a/libgitg/gitg-when-mapped.vala
+++ b/libgitg/gitg-when-mapped.vala
@@ -103,6 +103,7 @@ namespace Gitg
                        else
                        {
                                d_sid = d_widget.map.connect(() => {
+                                       d_widget.disconnect(d_sid);
                                        d_sid = 0;
 
                                        if (d_lifetime != null)