[mutter] cursor-tracker: Have one global cursor tracker

[Jasper St. Pierre <jstpierre src gnome org>]

commit ef44cc5a536f1d65b69dbf8f4898236df894d699
Author: Jasper St. Pierre <jstpierre mecheye net>
Date:   Tue Apr 22 11:28:13 2014 -0400

    cursor-tracker: Have one global cursor tracker
    
    Now that we have a global MetaScreen, we can simply have a global
    MetaCursorTracker as well. Keep the get_for_screen() API around for
    compatibility, though.

 src/backends/meta-cursor-tracker.c |   12 +++++-------
 src/core/screen-private.h          |    1 -
 2 files changed, 5 insertions(+), 8 deletions(-)
---
diff --git a/src/backends/meta-cursor-tracker.c b/src/backends/meta-cursor-tracker.c
index 56c1f6f..d348621 100644
--- a/src/backends/meta-cursor-tracker.c
+++ b/src/backends/meta-cursor-tracker.c
@@ -172,6 +172,8 @@ meta_cursor_tracker_new (MetaScreen *screen)
     return make_x11_cursor_tracker (screen);
 }
 
+static MetaCursorTracker *_cursor_tracker;
+
 /**
  * meta_cursor_tracker_get_for_screen:
  * @screen: the #MetaScreen
@@ -183,14 +185,10 @@ meta_cursor_tracker_new (MetaScreen *screen)
 MetaCursorTracker *
 meta_cursor_tracker_get_for_screen (MetaScreen *screen)
 {
-  MetaCursorTracker *self;
+  if (!_cursor_tracker)
+    _cursor_tracker = meta_cursor_tracker_new (screen);
 
-  if (screen->cursor_tracker)
-    return screen->cursor_tracker;
-
-  self = meta_cursor_tracker_new (screen);
-  screen->cursor_tracker = self;
-  return self;
+  return _cursor_tracker;
 }
 
 static void
diff --git a/src/core/screen-private.h b/src/core/screen-private.h
index ef279e5..364ca15 100644
--- a/src/core/screen-private.h
+++ b/src/core/screen-private.h
@@ -79,7 +79,6 @@ struct _MetaScreen
   MetaStack *stack;
   MetaStackTracker *stack_tracker;
 
-  MetaCursorTracker *cursor_tracker;
   MetaCursor current_cursor;
 
   Window wm_sn_selection_window;