src: guard against overflow in ParseArrayIndex() (v4.x)
Back-port of https://github.com/nodejs/node/pull/7497 and https://github.com/nodejs/node/pull/7587.
R=@TheAlphaNerd
Do not update/delete: Banner broadcast message test data
Do not update/delete: Notification broadcast message test data
Back-port of https://github.com/nodejs/node/pull/7497 and https://github.com/nodejs/node/pull/7587.
R=@TheAlphaNerd