all: remove some unused code

[sashamelentyev]

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Message from Go Bot:

Patch Set 1:

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Message from Ian Lance Taylor:

Patch Set 1:

(2 comments)

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This PR (HEAD: 48869f5) has been imported to Gerrit for code review.

Please visit https://go-review.googlesource.com/c/go/+/346231 to see it.

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Message from Ian Lance Taylor:

Patch Set 3: Run-TryBot+1

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Message from Go Bot:

Patch Set 3:

(1 comment)

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Message from Go Bot:

Patch Set 3: TryBot-Result+1

(1 comment)

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Message from Ian Lance Taylor:

Patch Set 3: Code-Review+2

(1 comment)

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Message from Keith Randall:

Patch Set 3: Trust+1

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This PR is being closed because golang.org/cl/346231 has been merged.