pgsql: - Check for NULL before checking whether argument is an

Log Message:
-----------
        - Check for NULL before checking whether argument is an array.
    - Removed stray character from string quoting.
    - Fixed check to report missing varchar pointer implementation.

Tags:
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REL8_0_STABLE

Modified Files:
--------------
    pgsql/src/interfaces/ecpg/ecpglib:
        data.c (r1.27 -> r1.27.4.1)
        (http://developer.postgresql.org/cvsweb.cgi/pgsql/src/interfaces/ecpg/ecpglib/data.c.diff?r1=1.27&r2=1.27.4.1)
    pgsql/src/interfaces/ecpg/preproc:
        preproc.y (r1.303.4.3 -> r1.303.4.4)

(http://developer.postgresql.org/cvsweb.cgi/pgsql/src/interfaces/ecpg/preproc/preproc.y.diff?r1=1.303.4.3&r2=1.303.4.4)