Bugfix: Correctly revert focus to other floating windows when closing a floating window

Uncovered by the testsuite \o/

src/randr.c

@@ -789,7 +789,7 @@ void randr_query_outputs() {
                 }
 
                 DLOG("destroying disappearing con %p\n", output->con);
-                tree_close(output->con, DONT_KILL_WINDOW, true);
+                tree_close(output->con, DONT_KILL_WINDOW, true, false);
                 DLOG("Done. Should be fine now\n");
                 output->con = NULL;
             }