Add META_TAB_LIST_NORMAL_ALL to MetaTabList enum

This is a new value, not associated with any keybindings, useful
when the WM needs to order the applications by last-interaction,
taking into account all windows.

https://bugzilla.gnome.org/show_bug.cgi?id=667552

src/core/display.c

@@ -4505,7 +4505,8 @@ get_focussed_group (MetaDisplay *display)
 
 #define IN_TAB_CHAIN(w,t) (((t) == META_TAB_LIST_NORMAL && META_WINDOW_IN_NORMAL_TAB_CHAIN (w)) \
     || ((t) == META_TAB_LIST_DOCKS && META_WINDOW_IN_DOCK_TAB_CHAIN (w)) \
-    || ((t) == META_TAB_LIST_GROUP && META_WINDOW_IN_GROUP_TAB_CHAIN (w, get_focussed_group(w->display))))
+    || ((t) == META_TAB_LIST_GROUP && META_WINDOW_IN_GROUP_TAB_CHAIN (w, get_focussed_group(w->display))) \
+    || ((t) == META_TAB_LIST_NORMAL_ALL && META_WINDOW_IN_NORMAL_TAB_CHAIN_TYPE (w)))
 
 static MetaWindow*
 find_tab_forward (MetaDisplay   *display,

src/core/keybindings.c

@@ -3019,6 +3019,8 @@ tab_op_from_tab_type (MetaTabList type)
       return META_GRAB_OP_KEYBOARD_TABBING_DOCK;
     case META_TAB_LIST_GROUP:
       return META_GRAB_OP_KEYBOARD_TABBING_GROUP;
+    case META_TAB_LIST_NORMAL_ALL:
+      break;
     }
 
   g_assert_not_reached ();
@@ -3037,6 +3039,8 @@ cycle_op_from_tab_type (MetaTabList type)
       return META_GRAB_OP_KEYBOARD_ESCAPING_DOCK;
     case META_TAB_LIST_GROUP:
       return META_GRAB_OP_KEYBOARD_ESCAPING_GROUP;
+    case META_TAB_LIST_NORMAL_ALL:
+      break;
     }
 
   g_assert_not_reached ();

src/meta/display.h

@@ -33,7 +33,8 @@ typedef enum
 {
   META_TAB_LIST_NORMAL,
   META_TAB_LIST_DOCKS,
-  META_TAB_LIST_GROUP
+  META_TAB_LIST_GROUP,
+  META_TAB_LIST_NORMAL_ALL
 } MetaTabList;
 
 typedef enum