Return FeeCalculator with TransactionResults to use in transaction_status_service

[CriesofCarrots]

Problem

This .expect() is reachable by a mainnet-beta validator:

solana/core/src/transaction_status_service.rs

Lines 65 to 71 in 6429042

	let fee_calculator = match hash_age_kind {
	Some(HashAgeKind::DurableNonce(_, account)) => {
	nonce_utils::fee_calculator_of(&account)
	}
	_ => bank.get_fee_calculator(&transaction.message().recent_blockhash),
	}
	.expect("FeeCalculator must exist");

Summary of Changes

Return FeeCalculators used in processing transactions with TransactionResults, ensuring that if the transaction assessed fees successfully, the FeeCalculator is available for the TransactionStatusService.

Caveat: So far I haven't been able to write a test that fails on that expect.
A recent_blockhash transaction doesn't hit this exception, even if the blockhash is relatively old, because the bank uses the stricter MAX_PROCESSING_AGE to pass/fail transactions, so the recent_blockhash can be at worst in the middle of the bank's blockhash_queue.

Nonce transactions seem more suspicious, but I didn't come up with a failure case. I tried to remove a nonce account immediately after using it, before pulling the fee calculator from that bank, and the removal was caught by this error:

solana/sdk/src/nonce/account.rs

Line 90 in 17a8cc8

return Err(NonceError::NotExpired.into());

I didn't think of any other legitimate way to make the nonce account fee calculator unavailable, short of data corruption; advancing the nonce account doesn't hit the exception, since fee_calculator_of actually doesn't care if it's returning the right fee calculator (I think this could lead to incorrect nonced-tx fees being cached in Blockstore).

I still think this pr makes this area more robust, and if nothing else it resolves the potential issue with nonce transactions caching incorrect fee data in TSS.

Fixes #10958

[CriesofCarrots]

@mvines , thoughts?
@t-nelson , am I right about the nonced-tx fee calculator issue? (I will add a test)

[t-nelson]

@t-nelson , am I right about the nonced-tx fee calculator issue? (I will add a test)

Sounds right. fee_calculator_of() was written under the assumption that it be used in the context of a validated nonce transaction referencing the given account. If the bank the account is queried from isn't frozen, that assumption won't hold

[codecov]

Codecov Report

Merging #10967 into master will decrease coverage by 0.0%.
The diff coverage is 100.0%.

@@            Coverage Diff            @@
##           master   #10967     +/-   ##
=========================================
- Coverage    82.1%    82.1%   -0.1%     
=========================================
  Files         318      318             
  Lines       72747    72741      -6     
=========================================
- Hits        59777    59770      -7     
- Misses      12970    12971      +1     

[CriesofCarrots]

Nonce issue described is not actually an issue, as the fee calculator is pulled from the actual account in HashAgeKind::DurableNonce.

[stale]

This pull request has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs.