fix(core,eth/tracers): resolve coinbase owner per transaction

[gzliudan]

Proposed changes

Resolve the coinbase owner inside ApplyTransactionWithEVM instead of passing a precomputed value from block processing.

This keeps fee routing aligned with the active state for each transaction and makes the block execution and tracer paths use the same owner-resolution logic.

Ref: #649

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Impacted Components

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• Consensus
• Account
• Network
• Geth
• Smart Contract
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• This PR has sufficient test coverage (unit/integration test) OR I have provided reason in the PR description for not having test coverage
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• Tested the backwards compatibility.
• Tested with XDC nodes running this version co-exist with those running the previous version.
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[Copilot]

Pull request overview

This PR fixes incorrect fee recipient behavior during block processing by ensuring the coinbase “owner” is resolved from state for each transaction (instead of being computed once before iterating the block’s transactions). This prevents fee credits from going to a stale owner if the owner mapping changes mid-block.

Changes:

• Move coinbase owner lookup into ApplyTransactionWithEVM so it is refreshed per transaction.
• Remove the now-unneeded getCoinbaseOwner helper and adjust internal call sites accordingly.
• Update unit tests to match the new ApplyTransactionWithEVM function signature.

Reviewed changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated 2 comments.

File	Description
core/state_processor.go	Computes coinbase owner inside ApplyTransactionWithEVM per-tx; removes helper; updates callers.
core/state_processor_test.go	Updates tests to call ApplyTransactionWithEVM with the new signature.

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[Copilot]

Pull request overview

Copilot reviewed 3 out of 3 changed files in this pull request and generated 2 comments.

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[Copilot]

Pull request overview

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[wanwiset25]

is this potential fork?
how does Ethereum do it?

[Copilot]

Pull request overview

Copilot reviewed 3 out of 3 changed files in this pull request and generated no new comments.

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[gzliudan]

is this potential fork? how does Ethereum do it?

A consensus difference is triggered only if all of the following conditions hold:

The block is after TIPTRC21Fee, because only after that point normal transaction fees are credited to the validator owner rather than directly to coinbase.

The current block producer address, meaning the current coinbase, has an owner entry in XDCValidator state, since fee routing reads validatorsState[coinbase].owner.

Earlier in the same block, a transaction changes the owner result for that same current coinbase, or deletes its validator record entirely.

After that owner-changing transaction, the block still contains at least one later normal transaction that goes through the ordinary fee-credit path.

That combination matters because the old code resolved the coinbase owner once at block start and reused it for the whole block, while acf6ebd2 resolves the owner again from the current state before each transaction. If the owner changes mid-block, later transaction fees are credited to a different recipient, which changes balances and therefore changes the state root.

In XDCValidator, the functions that can change the owner outcome are:

propose(address _candidate)

This writes a new validator record with owner: msg.sender, so it explicitly sets validatorsState[_candidate].owner to a new address.

voteInvalidKYC(address _invalidCandidate)

When the threshold is reached, this deletes validator records for the invalidated owner’s candidates. That does not assign a new nonzero owner, but it does change the effective owner lookup result, because reading validatorsState[candidate].owner afterward returns the zero address.

Other functions such as vote, unvote, and resign do not rewrite the owner field itself. resign changes candidate status and stake-related fields, but it does not assign a new owner.

For the current block producer specifically, the more realistic trigger is voteInvalidKYC, not propose. propose requires onlyNotCandidate(_candidate), so it normally cannot be used to reset the owner of an already active validator that is currently producing the block.

This can only cause a consensus difference if, within the same block, the owner lookup result for the current block producer changes before later normal transactions are executed. In practice, for the current coinbase, that would realistically require a voteInvalidKYC transaction. While propose can also write a new owner in XDCValidator, it requires onlyNotCandidate(_candidate), so it is normally not applicable to an already active block-producing validator. As a result, voteInvalidKYC is the practical trigger for a mid-block owner change that could make pre- and post-acf6ebd2 nodes credit transaction fees to different recipients and derive different state roots.