Avoid `Value::BooleanValue` calls
Avoid `Value::BooleanValue` calls

Back in 2015, the v8/v8 repository gained a variety of maybe
methods. One of those was for `Value::BooleanValue` back in
commit `8d839ea` which was released with V8 v4.3.11 (pre-Node.js v4).
The non-maybe version was set as `V8_DEPRECATE_SOON` back in
V8 v4.3.27 (`47154aa`) as well. It has finally been removed
from V8 and Node.js v12 (upcoming LTS) ships with this updated V8.

Really, those calls are just checks for whether the values
have been set, so we can just check for their types to match
our expectations.

Ref: https://chromium.googlesource.com/v8/v8.git/+/8d839ead046f3b377135509a2264a9e5fecc98ba
Ref: https://chromium.googlesource.com/v8/v8.git/+/47154aa8b2564ccb72e233a6c3c449c8edb53001
Change-Id: If074d3b749dc60a36dfc4fc001f486c683935278
Reviewed-on: http://review.couchbase.org/110171
Reviewed-by: Brett Lawson <c8c4369773d7d7226e031f0c4af62e3f38a08510@gmail.com>
Tested-by: Brett Lawson <c8c4369773d7d7226e031f0c4af62e3f38a08510@gmail.com>

couchbase/couchnode,brett19/couchnode,couchbase/couchnode,brett19/couchnode,brett19/couchnode,couchbase/couchnode,couchbase/couchnode