Fix crash in EffectWindow::visibleInClientGroup() when it's called on a

window that doesn't have a decoration.
BUG: 214757

svn path=/trunk/KDE/kdebase/workspace/; revision=1049896

effects.cpp

@@ -1516,7 +1516,11 @@ void EffectWindowImpl::closeWindow() const
 bool EffectWindowImpl::visibleInClientGroup() const
     {
     if( Client* c = dynamic_cast< Client* >( toplevel ))
+        {
+        if( !c->clientGroup() )
+            return true;
         return c == c->clientGroup()->visible();
+        }
     return false;
     }