Add PublicKeyCodec

[aaronc]

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

This adds:

• a crypto/types.PublicKeyCodec interface for marshaling crypto.PubKeys to and from the protobuf PublicKey representation
• std.DefaultPublicKeyCodec which supports the standard public key types supported by the SDK

---

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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

[codecov]

Codecov Report

Merging #6372 into master will decrease coverage by 4.14%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##           master    #6372      +/-   ##
==========================================
- Coverage   55.61%   51.46%   -4.15%     
==========================================
  Files         454      297     -157     
  Lines       27360    17022   -10338     
==========================================
- Hits        15215     8761    -6454     
+ Misses      11050     7673    -3377     
+ Partials     1095      588     -507     

[tac0turtle]

utACK, I will add to the tendermint tracking issue that the key types have been migrated to []byte. Do you still need to register the old keys in a amino codec?

[fedekunze]

utACK

[aaronc]

utACK, I will add to the tendermint tracking issue that the key types have been migrated to []byte. Do you still need to register the old keys in a amino codec?

Yes, for now we are providing amino backwards compatibility.

[tac0turtle]

Yes, for now we are providing amino backwards compatibility.

you will then have to provide a cryptoamino codec similar to the one called from Tendermint. We are removing amino entirely.

[aaronc]

Yes, for now we are providing amino backwards compatibility.

you will then have to provide a cryptoamino codec similar to the one called from Tendermint. We are removing amino entirely.

We've already added one ;)