Update ante handlers to use SignatureV2

[aaronc]

This is one of several bite-size PR's that are being pulled out of #6216 to implement #6213.

This PR:

• SigVerificationDecorator and SigGasConsumeDecorator now work with the SignatureV2 infrastructure introduced in Add SignatureV2 infrastructure #6373 .
• SignatureVerificationGasConsumer now has the signature: func(meter sdk.GasMeter, sig signing.SignatureV2, params types.Params) error.
• NewAnteHandler and NewSigVerificationDecorator both now take a SignModeHandler parameter.
• The SigVerifiableTx interface now has a GetSignaturesV2() ([]signing.SignatureV2, error) method and no longer has GetSignatures and GetSignBytes methods.

---

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[codecov]

Codecov Report

Merging #6428 into master will decrease coverage by 5.94%.
The diff coverage is 69.13%.

@@            Coverage Diff             @@
##           master    #6428      +/-   ##
==========================================
- Coverage   62.79%   56.85%   -5.95%     
==========================================
  Files         251      479     +228     
  Lines       16306    28796   +12490     
==========================================
+ Hits        10240    16371    +6131     
- Misses       5361    11268    +5907     
- Partials      705     1157     +452     

[aaronc]

It would be great if someone else familiar with the ante handler stack could take a look at this @alexanderbez @alessio @jgimeno. It’s in the critical path for the proto migration

[AdityaSripal]

The decorators all look correct to me. Is this intended to be a backwards-compatible change?

If so, would it make more sense to implement these as separate decorators SigVerificationV2Decorator, so that people could use the old versions if they wish?

would prefer an approval from one of the SDK code owners before merging

[aaronc]

The decorators all look correct to me. Is this intended to be a backwards-compatible change?

If so, would it make more sense to implement these as separate decorators SigVerificationV2Decorator, so that people could use the old versions if they wish?

It should be backwards compatible as is. i.e. these decorators are doing the exact same thing they were before except using an API that also supports proto tx’s. So l don’t think making them separate decorators is actually necessary.

Thanks for reviewing the logic!

[alexanderbez]

ACK