core/vm: clean up EVM environmental structure

[rjl493456442]

This PR does a few things including:

• Remove ContractRef interface
• Remove vm.AccountRef which implements ContractRef interface
• Maintain the jumpDests struct in EVM for sharing between call frames
• Simplify the delegateCall context initialization

[rjl493456442]

I will setup a full sync to ensure nothing is broken. As the changes touch very core part.

https://my.papertrailapp.com/systems/13274397401/events

[MariusVanDerWijden]

In general LGTM, a great idea and makes stuff a lot cleaner, there was just two things that I wanted to talk about before merging (not really related to this PR, just the code in general)

[MariusVanDerWijden]

This was never used, right? weird...

[rjl493456442]

I don't know... At least it's not used now

[MariusVanDerWijden]

LGTM

For everyone else reviewing this, we slightly change the behavior with this.
Previously a contract created by CREATE2 would cache the jumpdest analysis for the initcode, while a contracted created by CREATE would not. Now both contracts will NOT cache the jumpdest analysis for initcode. Since it is very unlikely for two initcodes to be exactly the same, and in the case of an attack its very easy to circumvent this, its better not to bloat the memory with unusable jumpdest analyses