Use eth_chainId when signing transactions

[cgewecke]

Addresses #2378 and #1169 for the 1.x branch. Makes web3 conform to EIP 155 and fetch chainId via eth_chainId instead of net_version. For ethereum public nets there's no problem here because network id == chain id. For ganache, ETC and possibly others - the two values are different.

Note: these endpoints return their ids in different formats:

Client	net_version	eth_chainId
geth --dev	"1337"	"0x539"
parity --dev	"17"	"0x11"
ganache-cli	"1570135120814"	"0x539"

eth_chainId is not documented in the JSON_RPC spec. This is a case where it would be nice to have E2E tests vs the three main clients to be sure Web3's mocked responses correspond to reality.

[coveralls]

Coverage remained the same at 83.02% when pulling 7e3f319 on cgewecke:issue/2378 into 139144e on ethereum:1.x.

[gabmontes]

@cgewecke these changes are good IMHO.

I've been patching beta 37 with this exact set of changes in several Metronome projects for quite some time and works flawlessly.

Hope this is merged soon.

[cgewecke]

Thanks @gabmontes, good to know.

[nivida]

Could you update the changelog for this and all other PRs you proposed?

[cgewecke]

@nivida Do want the changelog updated under 1.2.2? Or unreleased?

[nivida]

„Unreleased“ is just the tag to label the unreleased version and the related changes. You can just extend the list of 1.2.2. @cgewecke

[cgewecke]

@nivida Oh I just remembered something - not sure how you do this exactly but there is a nice npm utility called changelog that helps you generate a version-based changelog in one post-publication step.

The output still needs to be edited etc, but it seems like a convenient way of avoiding merge conflicts when there are lots of small PRs queued up like this and they all modify the same file.

[nivida]

@cgewecke Let us discuss this in an issue. :)