pgsql: Add: > > * Change memory allocation for multi-byte functions so

Log Message:
-----------
Add:

* Change memory allocation for multi-byte functions so memory is
allocated inside conversion functions

Currently we preallocate memory based on worst-case usage.

Modified Files:
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pgsql/doc:
TODO (r1.2299 -> r1.2300)
(http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/doc/TODO?r1=1.2299&r2=1.2300)
pgsql/doc/src/FAQ:
TODO.html (r1.808 -> r1.809)
(http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/doc/src/FAQ/TODO.html?r1=1.808&r2=1.809)