fix: fix wrong stream canceled up after cloning (v6)

[snyamathi]

This relates to...

• [PPR] TypeError: Response.clone: Body has already been consumed. vercel/next.js#69635
• use FinalizationRegistry for cloned response body #3458

Rationale

The request/stream registered with the finalization registry is mixed up between the clone and the original request.

Changes

This PR just changes which of the two tee'd streams is associated

edit: updated with changes from @tsctx how we're fixing the stream registration is moved to a better location #4419

Features

N/A

Bug Fixes

See changes above

Breaking Changes and Deprecations

N/A

Status

• I have read and agreed to the Developer's Certificate of Origin
• Tested
• Benchmarked (optional)
• Documented
• Review ready
• In review
• Merge ready

[Copilot]

Pull Request Overview

Fixes a bug where the wrong stream was being registered with the finalization registry when cloning Response objects. This was causing premature cancellation of the original response's stream when the cloned response was garbage collected.

• Changed the stream registration from out1 to out2 in the clone body logic
• Added a test to verify that garbage collection of a clone doesn't affect the original response

Reviewed Changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated 1 comment.

File	Description
lib/web/fetch/body.js	Fixed stream registry to register the correct stream (out2 instead of out1) for the cloned instance
test/fetch/response.js	Added test to verify that garbage collection of cloned response doesn't break the original response

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[Uzlopak]

RSLGTM

[Uzlopak]

Merging as the failed CI is unrelated.