TokenNetworkRegistry should check the deprecation executor address before/after sending a tx

[pirapira]

This issue keeps track of making sure that the TokenNetworkRegistry's proxy checks the deprecation executor address before sending createERC20TokenNetwork() transaction. Also check the same condition after gas estimation or the tx in a block fails.

These checks are necessary because the function fails when the deprecation executor address is zero.

[pirapira]

This is a part of #4792.

[rakanalh]

https://github.com/raiden-network/raiden-contracts/blob/94f1428d2fad4719efffb26be3d7731d7bb3f3da/raiden_contracts/data/source/raiden/TokenNetworkRegistry.sol#L70-L105

The contract seems to set the deprecation_executor to msg.sender but the value isn't used in a modifier to disable adding new token networks. Should this be done in the contracts first?

[pirapira]

I noticed @rakanalh is already working on this issue in #4936.

[pirapira]

The contract seems to set the deprecation_executor to msg.sender but the value isn't used in a modifier to disable adding new token networks. Should this be done in the contracts first?

I think that's a good idea.