kvserver: fix the log tag on split

[andreimatei]

Make the initial lease application on the RHS after a split reflect the
fact that it's executing in the context of the RHS, not the LHS.

Release note: None

[cockroach-teamcity]

This change is 

[nvb]

Reviewable status: complete! 0 of 0 LGTMs obtained (waiting on @andreimatei and @tbg)

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pkg/kv/kvserver/store_split.go, line 278 at r1 (raw file):

	rightRepl.mu.Lock()
	defer rightRepl.mu.Unlock()
	ctx = logtags.AddTag(ctx, "r", rightRepl.RangeID)

Can we use the RHS's AmbientContext for this?

[andreimatei]

Reviewable status: complete! 0 of 0 LGTMs obtained (waiting on @nvanbenschoten and @tbg)

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pkg/kv/kvserver/store_split.go, line 278 at r1 (raw file):

Previously, nvanbenschoten (Nathan VanBenschoten) wrote…

Can we use the RHS's AmbientContext for this?

ya, done

[nvb]

Reviewed 1 of 2 files at r2.
Reviewable status: complete! 0 of 0 LGTMs obtained (waiting on @andreimatei and @tbg)

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pkg/kv/kvserver/replica_proposal.go, line 306 at r2 (raw file):

	ctx context.Context, newLease roachpb.Lease, permitJump bool,
) {
	ctx = r.AnnotateCtx(ctx)

Let's keep this in prepareRightReplicaForSplit. That's the only case where the context won't already be properly annotated.

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pkg/kv/kvserver/store_split.go, line 278 at r1 (raw file):

Previously, andreimatei (Andrei Matei) wrote…

ya, done

Did you confirm that the AmbientContext can be used to overwrite an existing log tag?

[andreimatei]

Reviewable status: complete! 0 of 0 LGTMs obtained (waiting on @nvanbenschoten)

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pkg/kv/kvserver/store_split.go, line 278 at r1 (raw file):

Previously, nvanbenschoten (Nathan VanBenschoten) wrote…

Did you confirm that the AmbientContext can be used to overwrite an existing log tag?

I did. This is also documented a few layers down, here

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pkg/kv/kvserver/replica_proposal.go, line 306 at r2 (raw file):

Previously, nvanbenschoten (Nathan VanBenschoten) wrote…

Let's keep this in prepareRightReplicaForSplit. That's the only case where the context won't already be properly annotated.

done