Bug 630000 - crash [@ NotificationController::Shutdown()], r=davidb, sr=neil, a=davidb

accessible/src/base/NotificationController.cpp

@@ -77,7 +77,8 @@ NS_IMPL_RELEASE(NotificationController)
 NS_IMPL_CYCLE_COLLECTION_CLASS(NotificationController)
 
 NS_IMPL_CYCLE_COLLECTION_UNLINK_BEGIN_NATIVE(NotificationController)
-  tmp->Shutdown();
+  if (tmp->mDocument)
+    tmp->Shutdown();
 NS_IMPL_CYCLE_COLLECTION_UNLINK_END
 
 NS_IMPL_CYCLE_COLLECTION_TRAVERSE_NATIVE_BEGIN(NotificationController)

accessible/src/base/nsDocAccessible.cpp

@@ -146,7 +146,6 @@ NS_IMPL_CYCLE_COLLECTION_TRAVERSE_BEGIN_INHERITED(nsDocAccessible, nsAccessible)
 NS_IMPL_CYCLE_COLLECTION_TRAVERSE_END
 
 NS_IMPL_CYCLE_COLLECTION_UNLINK_BEGIN_INHERITED(nsDocAccessible, nsAccessible)
-  tmp->mNotificationController->Shutdown();
   NS_IMPL_CYCLE_COLLECTION_UNLINK_NSCOMPTR(mNotificationController)
   NS_IMPL_CYCLE_COLLECTION_UNLINK_NSTARRAY(mChildDocuments)
   tmp->mDependentIDsHash.Clear();