[RFA] Remove two cleanups using std::string

[Tom Tromey]

>>>>> "Simon" == Simon Marchi <simark@simark.ca> writes:

Simon> LGTM.  I would be more confident if that non-trivial escaping code was
Simon> unit-tested, but I tried it by hand and it seems to do what it's supposed
Simon> to do.

Yeah.  I looked at this briefly but it seemed like a lot of work for not
a huge benefit.  Maybe if some other code was doing the same thing, it
would make sense to pull this logic out into its own function.

Tom