[cherry-picked] abci: Vote Extension 1 (#6646)

* add proto, add boilerplates

* add canonical

* fix tests

* add vote signing test

* Update internal/consensus/msgs_test.go

* modify state execution in progress

* add extension signing

* VoteExtension -> ExtendVote

* apply review

* update data structures

* Add comments

* Apply suggestions from code review

Co-authored-by: Aleksandr Bezobchuk <alexanderbez@users.noreply.github.com>

* *Signed -> *ToSign

* add Vote to RequestExtendVote

* apply reviews

* Apply suggestions from code review

Co-authored-by: Dev Ojha <ValarDragon@users.noreply.github.com>
Co-authored-by: Aleksandr Bezobchuk <alexanderbez@users.noreply.github.com>

* fix typo, modify proto

Co-authored-by: Aleksandr Bezobchuk <alexanderbez@users.noreply.github.com>
Co-authored-by: Dev Ojha <ValarDragon@users.noreply.github.com>

state/execution.go

@@ -293,6 +293,19 @@ func (blockExec *BlockExecutor) ApplyBlock(
 	return state, nil
 }
 
+func (blockExec *BlockExecutor) ExtendVote(vote *types.Vote) (types.VoteExtension, error) {
+	req := abci.RequestExtendVote{
+		Vote: vote.ToProto(),
+	}
+
+	resp, err := blockExec.proxyApp.ExtendVoteSync(req)
+	if err != nil {
+		return types.VoteExtension{}, err
+	}
+
+	return types.VoteExtensionFromProto(resp.VoteExtension), nil
+}
+
 // Commit locks the mempool, runs the ABCI Commit message, and updates the
 // mempool.
 // It returns the result of calling abci.Commit (the AppHash) and the height to retain (if any).
@@ -473,7 +486,7 @@ func updateState(
 
 	nextVersion := state.Version
 
-	// NOTE: the AppHash has not been populated.
+	// NOTE: the AppHash and the VoteExtension has not been populated.
 	// It will be filled on state.Save.
 	return State{
 		Version:                          nextVersion,

state/execution_test.go

@@ -178,11 +178,15 @@ func TestFinalizeBlockValidators(t *testing.T) {
 		commitSig0 = types.NewCommitSigForBlock(
 			[]byte("Signature1"),
 			state.Validators.Validators[0].Address,
-			now)
+			now,
+      types.VoteExtensionToSign{},
+    )
 		commitSig1 = types.NewCommitSigForBlock(
 			[]byte("Signature2"),
 			state.Validators.Validators[1].Address,
-			now)
+			now,
+      types.VoteExtensionToSign{},
+    )
 		absentSig = types.NewCommitSigAbsent()
 	)