When tracing references, reset the type and size of tuples allocated

from the fast free list -- the type (at least) is reset by
_Py_Dealloc().

Objects/tupleobject.c

@@ -73,6 +73,10 @@ PyTuple_New(size)
 		free_tuples[size] = (PyTupleObject *) op->ob_item[0];
 #ifdef COUNT_ALLOCS
 		fast_tuple_allocs++;
+#endif
+#ifdef Py_TRACE_REFS
+		op->ob_type = &PyTuple_Type;
+		op->ob_size = size;
 #endif
 	}
 	else