Added a "new_shares" attribute inside the delegate event type

[RiccardoM]

Description

This PR adds a new attribute inside the event types delegate. This is useful to return the new shares amount that cannot be queried otherwise without having to perform a new gRPC query.

The rationale behind this is to allow state parsers (such as BDJuno) to handle properly the MsgDelegate parsing, storing a new row that represents the delegation and its associated shares amount.

Currently, in order to do so we have to query the gRPC to get the shares amount. With this change, this won't be needed anymore as the new shares amount will be returned inside the event itself.

closes: #XXXX

---

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• Targeted PR against correct branch (see CONTRIBUTING.md)
• Linked to Github issue with discussion and accepted design OR link to spec that describes this work.
• Code follows the module structure standards.
• Wrote unit and integration tests
• Updated relevant documentation (docs/) or specification (x/<module>/spec/)
• Added relevant godoc comments.
• Added a relevant changelog entry to the Unreleased section in CHANGELOG.md
• Re-reviewed Files changed in the Github PR explorer
• Review Codecov Report in the comment section below once CI passes

[codecov]

Codecov Report

Merging #9214 (e46d7d6) into master (6ad84c5) will decrease coverage by 0.00%.
The diff coverage is 0.00%.

@@            Coverage Diff             @@
##           master    #9214      +/-   ##
==========================================
- Coverage   60.03%   60.03%   -0.01%     
==========================================
  Files         595      595              
  Lines       37352    37353       +1     
==========================================
  Hits        22425    22425              
- Misses      12939    12940       +1     
  Partials     1988     1988              

Impacted Files	Coverage Δ
x/staking/keeper/msg_server.go	0.45% <0.00%> (-0.01%)	⬇️

[amaury1093]

okay for me

[amaury1093]

Could you add a changelog entry?

[RiccardoM]

Could you add a changelog entry?

What tag should I use? And under which section?

[amaury1093]

Unreleased > Features seems the most logical to me

[cyberbono3]

LGTM

[RiccardoM]

Unreleased > Features seems the most logical to me

Added 👍

[alexanderbez]

We explicitly removed the concept of "shares" from all UX surface long ago. Was there a reason you needed this @RiccardoM?

[RiccardoM]

We explicitly removed the concept of "shares" from all UX surface long ago. Was there a reason you needed this @RiccardoM?

Many explorers still use this to calculate the self delegate ratio of a validator. If you think there's a better way to do this, then this commit can get reverted

[alexanderbez]

Why can you not take their self-delegation / total-delegation?

[RiccardoM]

Why can you not take their self-delegation / total-delegation?

Actually, you're right. I thought that shares were still useful to determine whether a validator was slashes in the past or not (since the share/token ratio would increase in that case). But I think we can simply get the past events and see if there was a slashing event I guess.

Feel free to revert this change if you think it's useless and/or might make things more complicated UX-wise

[alexanderbez]

Ehh there's no harm :)