merge revision(s) 97449338d6cb42d9dd7c9ca61550616e7e6b6ef6: [Backport #20649]
[Bug #20649] Allow `nil` as 2nd argument of `assign_error` Fallback to the last token element in that case, for the backward compatibilities.
merge revision(s) 97449338d6cb42d9dd7c9ca61550616e7e6b6ef6: [Backport #20649]