[gnome-builder] workbench: add fallbacks to more reliable close

[Christian Hergert <chergert src gnome org>]

commit 3552b8b403673794929ef34840a23ea53fc570fb
Author: Christian Hergert <christian hergert me>
Date:   Mon Mar 30 13:53:29 2015 -0700

    workbench: add fallbacks to more reliable close
    
    If we get stuck somehow, at least close the damn window.

 src/workbench/gb-workbench.c |   14 +++++++++++---
 1 files changed, 11 insertions(+), 3 deletions(-)
---
diff --git a/src/workbench/gb-workbench.c b/src/workbench/gb-workbench.c
index ad957e3..a75273c 100644
--- a/src/workbench/gb-workbench.c
+++ b/src/workbench/gb-workbench.c
@@ -98,13 +98,21 @@ gb_workbench_delete_event (GtkWidget   *widget,
   if (self->unloading)
     {
       /* Second attempt to kill things, cancel clean shutdown */
-      g_cancellable_cancel (self->unload_cancellable);
-      return TRUE;
+      if (!g_cancellable_is_cancelled (self->unload_cancellable))
+        {
+          g_cancellable_cancel (self->unload_cancellable);
+          return TRUE;
+        }
+
+      /* third attempt, kill it */
+      return FALSE;
     }
 
+  g_assert_cmpint (self->unloading, ==, FALSE);
+
   if (self->context != NULL)
     {
-      g_assert (!self->unload_cancellable);
+      g_assert (self->unload_cancellable == NULL);
 
       self->unloading = TRUE;
       self->unload_cancellable = g_cancellable_new ();