pgsql: Fix REASSIGN OWNED so that it works on procedural languages too.

Log Message:
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Fix REASSIGN OWNED so that it works on procedural languages too.

The capability for changing language owners is new in 8.3, so that's how
far back this needs to be backpatched.

Per bug #4132 by Kirill Simonov.

Modified Files:
--------------
    pgsql/src/backend/catalog:
        pg_shdepend.c (r1.26 -> r1.27)
        (http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/src/backend/catalog/pg_shdepend.c?r1=1.26&r2=1.27)
    pgsql/src/backend/commands:
        proclang.c (r1.77 -> r1.78)
        (http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/src/backend/commands/proclang.c?r1=1.77&r2=1.78)
    pgsql/src/include/commands:
        proclang.h (r1.12 -> r1.13)
        (http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/src/include/commands/proclang.h?r1=1.12&r2=1.13)