[gnome-tweak-tool] fix manual extension installation. Yay for 0 users that test this

[John Stowers <jstowers src gnome org>]

commit ca1a086ac21dbfb85ca910d43e0312d2e071e433
Author: John Stowers <john stowers gmail com>
Date:   Sun Mar 31 11:04:00 2013 +0200

    fix manual extension installation. Yay for 0 users that test this

 gtweak/tweaks/tweak_shell.py            |    2 +-
 gtweak/tweaks/tweak_shell_extensions.py |    2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)
---
diff --git a/gtweak/tweaks/tweak_shell.py b/gtweak/tweaks/tweak_shell.py
index 7de10b0..3f4bb33 100644
--- a/gtweak/tweaks/tweak_shell.py
+++ b/gtweak/tweaks/tweak_shell.py
@@ -135,7 +135,7 @@ class ShellThemeTweak(Tweak):
             chooser = FileChooserButton(
                         _("Select a theme"),
                         True,
-                        "application/zip")
+                        ["application/zip"])
             chooser.connect("file-set", self._on_file_set)
 
             self.widget = build_label_beside_widget(self.name, chooser, cb)
diff --git a/gtweak/tweaks/tweak_shell_extensions.py b/gtweak/tweaks/tweak_shell_extensions.py
index f4bee16..066456d 100644
--- a/gtweak/tweaks/tweak_shell_extensions.py
+++ b/gtweak/tweaks/tweak_shell_extensions.py
@@ -109,7 +109,7 @@ class _ShellExtensionInstallerTweak(Tweak):
         chooser = FileChooserButton(
                         _("Select an extension"),
                         True,
-                        "application/zip")
+                        ["application/zip"])
         chooser.connect("file-set", self._on_file_set)
 
         hb = Gtk.HBox(spacing=UI_BOX_SPACING)