Thread: pgsql: Set read_only = TRUE while evaluating input queries for

Log Message:
-----------
Set read_only = TRUE while evaluating input queries for ts_rewrite()
and ts_stat(), per my recent suggestion.  Also add a possibly-not-needed-
but-can't-hurt check for NULL SPI_tuptable, before we try to dereference
same.

Modified Files:
--------------
    pgsql/src/backend/utils/adt:
        tsquery_rewrite.c (r1.6 -> r1.7)
        (http://developer.postgresql.org/cvsweb.cgi/pgsql/src/backend/utils/adt/tsquery_rewrite.c?r1=1.6&r2=1.7)
        tsvector_op.c (r1.6 -> r1.7)
        (http://developer.postgresql.org/cvsweb.cgi/pgsql/src/backend/utils/adt/tsvector_op.c?r1=1.6&r2=1.7)