[polari] joinDialog: Don't focus back button on click

[Florian Müllner <fmuellner src gnome org>]

commit 134217e34437addeb28de2b460892669716c6d07
Author: Florian Müllner <fmuellner gnome org>
Date:   Mon Feb 8 00:23:16 2016 +0100

    joinDialog: Don't focus back button on click
    
    Just like the "Add Connection" button in commit 478131921, clicking the
    button will hide it, so there's no point in grabbing the keyboard focus.

 src/joinDialog.js |    3 ++-
 1 files changed, 2 insertions(+), 1 deletions(-)
---
diff --git a/src/joinDialog.js b/src/joinDialog.js
index 7eb9113..9e86876 100644
--- a/src/joinDialog.js
+++ b/src/joinDialog.js
@@ -35,7 +35,8 @@ const JoinDialog = new Lang.Class({
         // TODO: Is there really no way to do this in the template?
         let icon = new Gtk.Image({ icon_name: 'go-previous-symbolic' });
         this._backButton = new Gtk.Button({ image: icon,
-                                            valign: Gtk.Align.CENTER });
+                                            valign: Gtk.Align.CENTER,
+                                            focus_on_click: false });
         this.get_header_bar().pack_start(this._backButton);
 
         this._setupMainPage();