encoding/gob: fix copy-paste bug

[cuiweixie]

No description provided.

[gopherbot]

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[gopherbot]

Message from Gopher Robot:

Patch Set 1:

(1 comment)

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[gopherbot]

Message from Keith Randall:

Patch Set 1:

(1 comment)

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After addressing review feedback, remember to publish your drafts!

[gopherbot]

Message from Rob Pike:

Patch Set 1: Code-Review+2

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Please don’t reply on this GitHub thread. Visit golang.org/cl/764482.
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[gopherbot]

Message from Rob Pike:

Patch Set 1: -Code-Review

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Please don’t reply on this GitHub thread. Visit golang.org/cl/764482.
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