container/list: combining insert and remove operations while moving elements within a list.
container/list: combining insert and remove operations while moving elements within a list.

Fixes #27747

Change-Id: I843e9e121d33440648b364650ee8a8a1639a0144
GitHub-Last-Rev: c614e91e23d4d3dea80bc78886a1b7e96456596b
GitHub-Pull-Request: golang/go#28413
Reviewed-on: https://go-review.googlesource.com/c/144998
Reviewed-by: Robert Griesemer <a6752097faebf1f02d80107d77a9be009089afe3@golang.org>
Run-TryBot: Robert Griesemer <a6752097faebf1f02d80107d77a9be009089afe3@golang.org>
TryBot-Result: Gobot Gobot <66cb808b70d30c07676d5e946fee83fd561249e5@golang.org>

cloudflare/go,akutz/go,cloudflare/go,CAFxX/go,nawawi/go,josharian/go,akutz/go,cloudflare/go,CAFxX/go,golang/go,nawawi/go,nawawi/go,akutz/go,golang/go,nawawi/go,nawawi/go,cloudflare/go,akutz/go,josharian/go,golang/go,josharian/go,golang/go,josharian/go,cloudflare/go,josharian/go,CAFxX/go,cloudflare/go,akutz/go,CAFxX/go,josharian/go,cloudflare/go,nawawi/go,nawawi/go,golang/go,CAFxX/go,nawawi/go,akutz/go,golang/go,cloudflare/go,CAFxX/go,josharian/go,golang/go,golang/go,josharian/go,CAFxX/go,akutz/go,akutz/go,CAFxX/go