fix: eliminate fee double-charge by using configurable decorator

[JimLarson]

refs: #9036

Description

The replacement for MempoolFeeDecorator suggested in the cosmos-sdk 0.46 upgrade guide does not behave the same as MempoolFeeDecorator and led to Txs being double-charged for fees.

The new Cosmos 0.46 DeductFeeDecorator subsumes the functionality of the old DeductFeeDecorator as well as the old MempoolFeeDecorator. We had created a local variation of the old DeductFeeDecorator with a configurable fee collector account.

Instead of cloning the old MempoolFeeDecorator (#9045), which increases our maintenance burden, we made the new DeductFeeDecorator configurable (agoric-labs/cosmos-sdk#407), so we'll use that instead.

Security Considerations

Usual scrutiny.

Scaling Considerations

N/A

Documentation Considerations

N/A

Testing Considerations

Testing for #9045 confirmed our understanding of the double-charge, but and further confirmation of the fix in an e2e test is desired available in agoric-sdk/a3p-integration/proposals/a:upgrade-next/ante-fees.test.js.

Upgrade Considerations

State-machine breaking, but otherwise N/A

[JimLarson]

Note for reviewer - please confirm that cherry-pick of agoric-labs/cosmos-sdk#407 to Agoric-v0.46.16.2.x was done correctly.

[gibson042]

This looks good, but I'm unclear on the agoric-labs/cosmos-sdk tag naming convention. I also think its CHANGELOG-Agoric.md could be a bit better:

 # Changelog (Agoric fork)
 
 ## Unreleased
 
-### Improvements
-
-* (auth) [#407](https://github.com/agoric-labs/cosmos-sdk/pull/407) Configurable fee collector module account in DeductFeeDecorator.
-
 ### API Breaking
 
 * (auth, bank) Agoric/agoric-sdk#8989 Remove deprecated lien support
 
 ## `v0.46.16-alpha.agoric.2.1` - 2024-03-08
 
 ### Improvements
 
-* (auth) #??? Configurable fee collector module account in DeductFeeDecorator. (backport #407)
+* (auth) [#407](https://github.com/agoric-labs/cosmos-sdk/pull/407) Configurable fee collector module account in DeductFeeDecorator.
 
 ## `v0.46.16-alpha.agoric.2` - 2024-02-08

[gibson042]

Shouldn't the new tag be v0.46.16-alpha.agoric.3? I feel like I'm missing something.

[michaelfig]

.3 was already taken by future incompatible changes (waiting in the wings of an agoric-sdk PR, but I'm not sure which one). .2.1 implies the first published revision of .2, which is more accurate.

[JimLarson]

We can't use the current tip of Agoric since lien support was removed in agoric-labs/cosmos-sdk#385 (in accordance with #8988, which is on master but not cherry-picked into the upgrade-14 release branch). So we need to use a side branch of Agoric for the new fee decorator feature. Our naming convention is to use <cosmos-release>-alpha.agoric.N sequentially on Agoric, ...-alpha.agoric.N.M for sub-branches, and presumably ...N.M.P for sub-sub-branches, etc. I'll document the policy in that repo.

[gibson042]

This seems like commentary for pull requests rather than permanent baggage.

Suggested change

	// subsumes former MempoolFeeDecorator
	ante.NewDeductFeeDecoratorWithName(opts.AccountKeeper, opts.BankKeeper, opts.FeegrantKeeper, nil, opts.FeeCollectorName),
	ante.NewDeductFeeDecoratorWithName(opts.AccountKeeper, opts.BankKeeper, opts.FeegrantKeeper, nil, opts.FeeCollectorName),

[JimLarson]

Done.

[gibson042]

A few testing suggestions, but overall reaffirming approval.

[JimLarson]

@gibson042 Regarding CHANGELOG-Agoric.md in agoric-labs/cosmos-sdk, Agoric-v0.46.16.2.x branch - I messed up and forgot to create a working sub-branch and made the modifications in the above branch, and pushed it to origin, so there was no PR to mention. I tried to unwind it with a force-push, but the Agoric* prefix on the branch name prevented any modification except by PR. (Apparently the initial erroneous push was not subject to that check.) I considered pushing a PR to revert the modifications on the branch, then aother PR to redo the cherry-pick with the correct changelog entry - both of which would need review and approval - but that exceeded the monkey-business I was prepared to invest just to get the changelog perfect.