CBQE-0: fix undefinded variable

Change-Id: Iae4e5db679fcf366a48ce55c9fadd6a1f2f6c0ff
Reviewed-on: http://review.couchbase.org/26467
Reviewed-by: Iryna Mironava <irynamironava@yandex.ru>
Tested-by: Iryna Mironava <irynamironava@yandex.ru>