[mutter/gnome-3-16] backend-x11: Adapt commit 55fd05ea5 to the 3-16 branch

[Florian Müllner <fmuellner src gnome org>]

commit 833c6e2263e3ef3042a80c4da818be5ed3108c3a
Author: Florian Müllner <fmuellner gnome org>
Date:   Sun Aug 2 22:16:23 2015 +0200

    backend-x11: Adapt commit 55fd05ea5 to the 3-16 branch
    
    Still only compile-tested, but I was asked repeatedly to apply this
    patch to 3-16, so let's try again ...

 src/backends/x11/meta-backend-x11.c |   10 +++++++++-
 1 files changed, 9 insertions(+), 1 deletions(-)
---
diff --git a/src/backends/x11/meta-backend-x11.c b/src/backends/x11/meta-backend-x11.c
index 6e52a5a..3ff8431 100644
--- a/src/backends/x11/meta-backend-x11.c
+++ b/src/backends/x11/meta-backend-x11.c
@@ -141,7 +141,15 @@ translate_crossing_event (MetaBackendX11 *x11,
       return;
     }
 
-  enter_event->event = meta_backend_x11_get_xwindow (x11);
+  Window stage_window = meta_backend_x11_get_xwindow (x11);
+  if (enter_event->event != stage_window)
+    {
+      /* See above for the rationale for this... */
+      g_assert (!meta_is_wayland_compositor ());
+      enter_event->event = meta_backend_x11_get_xwindow (x11);
+      enter_event->event_x = enter_event->root_x;
+      enter_event->event_y = enter_event->root_y;
+    }
 }
 
 static void