diff -Nru gnome-control-center-3.6.3/debian/changelog gnome-control-center-3.6.3/debian/changelog
--- gnome-control-center-3.6.3/debian/changelog	2014-03-21 11:25:55.000000000 +0000
+++ gnome-control-center-3.6.3/debian/changelog	2014-04-10 15:25:34.000000000 +0000
@@ -1,3 +1,10 @@
+gnome-control-center (1:3.6.3-0ubuntu56) trusty; urgency=medium
+
+  * debian/patches/git_keyboard_grp_xkb_option.patch:
+    - take upstream's grp xkb option combo for modifier-only input switching
+
+ -- William Hua <william.hua@canonical.com>  Tue, 08 Apr 2014 01:03:33 +1200
+
 gnome-control-center (1:3.6.3-0ubuntu54) trusty; urgency=medium
 
   * debian/control.in, debian/gnome/control-center-data.install,
diff -Nru gnome-control-center-3.6.3/debian/patches/git_keyboard_grp_xkb_option.patch gnome-control-center-3.6.3/debian/patches/git_keyboard_grp_xkb_option.patch
--- gnome-control-center-3.6.3/debian/patches/git_keyboard_grp_xkb_option.patch	1970-01-01 00:00:00.000000000 +0000
+++ gnome-control-center-3.6.3/debian/patches/git_keyboard_grp_xkb_option.patch	2014-04-10 15:25:34.000000000 +0000
@@ -0,0 +1,83 @@
+From 5b98213b04627f57c55d54b10f03351c9381ccc9 Mon Sep 17 00:00:00 2001
+From: Rui Matos <tiagomatos@gmail.com>
+Date: Mon, 1 Apr 2013 20:22:16 +0200
+Subject: [PATCH] keyboard: Add the XKB option for the input source switch
+ shortcut
+
+Mutter now uses the "grp" XKB option to implement a special
+modifiers-only shortcut use by gnome-shell to switch input sources.
+
+https://bugzilla.gnome.org/show_bug.cgi?id=700346
+---
+ panels/keyboard/cc-keyboard-option.c | 34 ++++++++++++++++++++++++++++++++++
+ 1 file changed, 34 insertions(+)
+
+diff --git a/panels/keyboard/cc-keyboard-option.c b/panels/keyboard/cc-keyboard-option.c
+index 33cb415..7a94f66 100644
+--- a/panels/keyboard/cc-keyboard-option.c
++++ b/panels/keyboard/cc-keyboard-option.c
+@@ -39,6 +39,7 @@
+ 
+ #define XKB_OPTION_GROUP_LVL3 "lv3"
+ #define XKB_OPTION_GROUP_COMP "Compose key"
++#define XKB_OPTION_GROUP_GRP  "grp"
+ 
+ enum
+ {
+@@ -97,6 +98,32 @@ static const gchar *xkb_option_comp_whitelist[] = {
+   NULL
+ };
+ 
++/* This list must be kept in sync with what mutter is able to
++ * handle. */
++static const gchar *xkb_option_grp_whitelist[] = {
++  "grp:toggle",
++  "grp:lalt_toggle",
++  "grp:lwin_toggle",
++  "grp:rwin_toggle",
++  "grp:lshift_toggle",
++  "grp:rshift_toggle",
++  "grp:lctrl_toggle",
++  "grp:rctrl_toggle",
++  "grp:sclk_toggle",
++  "grp:menu_toggle",
++  "grp:caps_toggle",
++  "grp:shift_caps_toggle",
++  "grp:alt_caps_toggle",
++  "grp:alt_space_toggle",
++  "grp:ctrl_shift_toggle",
++  "grp:lctrl_lshift_toggle",
++  "grp:rctrl_rshift_toggle",
++  "grp:ctrl_alt_toggle",
++  "grp:alt_shift_toggle",
++  "grp:lalt_lshift_toggle",
++  NULL
++};
++
+ static GList *objects_list = NULL;
+ 
+ GType cc_keyboard_option_get_type (void);
+@@ -233,6 +260,8 @@ cc_keyboard_option_constructed (GObject *object)
+     self->whitelist = xkb_option_lvl3_whitelist;
+   else if (g_str_equal (self->group, XKB_OPTION_GROUP_COMP))
+     self->whitelist = xkb_option_comp_whitelist;
++  else if (g_str_equal (self->group, XKB_OPTION_GROUP_GRP))
++    self->whitelist = xkb_option_grp_whitelist;
+   else
+     g_assert_not_reached ();
+ 
+@@ -328,6 +357,11 @@ cc_keyboard_option_get_all (void)
+                                                "group", XKB_OPTION_GROUP_COMP,
+                                                "description", _("Compose Key"),
+                                                NULL));
++  objects_list = g_list_prepend (objects_list,
++                                 g_object_new (CC_TYPE_KEYBOARD_OPTION,
++                                               "group", XKB_OPTION_GROUP_GRP,
++                                               "description", _("Modifiers-only switch to next source"),
++                                               NULL));
+   return objects_list;
+ }
+ 
+-- 
+1.9.1
+
diff -Nru gnome-control-center-3.6.3/debian/patches/series gnome-control-center-3.6.3/debian/patches/series
--- gnome-control-center-3.6.3/debian/patches/series	2014-03-21 11:25:55.000000000 +0000
+++ gnome-control-center-3.6.3/debian/patches/series	2014-04-10 15:25:34.000000000 +0000
@@ -1,3 +1,4 @@
+git_keyboard_grp_xkb_option.patch
 0001-online-accounts-use-the-async-function-to-get-all-th.patch
 0001-rfkill-glib-Don-t-use-g_assert_not_reached-in-type_t.patch
 05_run_update_manager.patch