net/http2: pool transport gzip readers

[AlexanderYastrebov]

This is a copy of the CL 510255 with the difference that
it preserves use of fs.ErrClosed when reading after close.

Updates golang/go#61353

[gopherbot]

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[gopherbot]

Message from Gopher Robot:

Patch Set 1:

(1 comment)

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[gopherbot]

Message from Alexander Yastrebov:

Patch Set 1:

(1 comment)

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[gopherbot]

Message from Sean Liao:

Patch Set 2: Commit-Queue+1

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[gopherbot]

Message from Go LUCI:

Patch Set 2:

Dry run: CV is trying the patch.

Bot data: {"action":"start","triggered_at":"2025-10-08T20:32:55Z","revision":"8e3e4d8fcffc1ff884c8c9290d9b1865375baa7b"}

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Message from Sean Liao:

Patch Set 2: -Commit-Queue

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Message from Go LUCI:

Patch Set 2:

This CL has passed the run

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Message from Go LUCI:

Patch Set 2: LUCI-TryBot-Result+1

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[gopherbot]

Message from Sean Liao:

Patch Set 2:

(1 comment)

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