Validator Creation Updates

[alexanderbez]

Update validator creation flow:

• Remove NewMsgCreateValidatorOnBehalfOf and corresponding business logic
• Ensure the validator address equals the delegator address during
  MsgCreateValidator#ValidateBasic

closes: #3789

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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.

• Wrote tests

• Updated relevant documentation (docs/)

• Added entries in PENDING.md with issue #

• rereviewed Files changed in the github PR explorer

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For Admin Use:

• Added appropriate labels to PR (ex. wip, ready-for-review, docs)
• Reviewers Assigned
• Squashed all commits, uses message "Merge pull request #XYZ: [title]" (coding standards)

[codecov]

Codecov Report

Merging #3803 into develop will decrease coverage by 0.09%.
The diff coverage is 66.66%.

@@            Coverage Diff            @@
##           develop   #3803     +/-   ##
=========================================
- Coverage    60.99%   60.9%   -0.1%     
=========================================
  Files          191     191             
  Lines        14177   14172      -5     
=========================================
- Hits          8647    8631     -16     
- Misses        4976    4985      +9     
- Partials       554     556      +2

[jackzampolin]

What about Ensure you cannot edit a validator if self-delegation is below minimum and testing? It looks like you have updated existing tests in this PR.

[alexanderbez]

@jackzampolin let me check if there is a test that covers the case if a delegation is below the min self delegation 👍 (if not, I'll add one).

[cwgoes]

Two tiny nits - otherwise ACK - but I don't think this closes #3789, it doesn't prevent editing a validator below minimum self-delegation (although I don't think we need to do that, but it's listed in the original issue).

[alexanderbez]

@jackzampolin there already is a test case in TestMsgCreateValidator for what you suggested. @cwgoes I intentionally left out the edit validator part. That needs more discussion.

[cwgoes]

Thanks @alexanderbez; my approval stands.

[jackzampolin]

This gets a 👍 LGTM from me!