Removed direct uses of CouchbaseImpl from ViewQuery.

Change-Id: I59ad983eec75a5dee0a85d3f019f9cc304fa4c83
Reviewed-on: http://review.couchbase.org/31000
Reviewed-by: Mark Nunberg <mnunberg@haskalah.org>
Tested-by: Brett Lawson <brett19@gmail.com>