Napi version in node-gyp

[mhdawson]

For discussion in next meeting:

nodejs/node-gyp#1745

[jschlight]

With node-pre-gyp and prebuild, the N-API version is essentially specified by the user and then the actual N-API version being built against is communicated into the binding.gyp file using a new napi-build-version variable we created for the purpose.

In the linked issue, the user is requesting that node-gyp inform the binding.gyp file which N-API version is supported by the version of Node being built against.

It's like the opposite of what we implemented for node-pre-gyp and prebuild.

[richardlau]

A PR was opened against core: nodejs/node#27800

[NickNaso]

Hi everyone,
I closed my previous PR and reopened new one nodejs/node#27835. Please if you have time take a look.

[NickNaso]

Hi everyone,
if someone has time could take a look at this PR nodejs/node#27835 in particular the last two comments? I need a feedback.

[NickNaso]

I’m closing this because the PR has been landed yesterday and the work now is on Node.js 12.6.0