[release-branch.go1.24] os: set full name for Roots created with Root.OpenRoot
Set the Name for a Root created within a Root to be the
concatenation of the parent's path and the name used to open the child.
This matches the behavior for files opened within a Root
with Root.Open.
For #73868
Fixes #75138
Change-Id: Idf4021602ac25556721b7ef6924dec652c7bf4db
Reviewed-on: https://go-review.googlesource.com/c/go/+/698376
Reviewed-by: Alan Donovan <adonovan@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
(cherry picked from commit
ed7f804775725149088a71108efd0b20ef9f206f)
Reviewed-on: https://go-review.googlesource.com/c/go/+/704278
Auto-Submit: Michael Knyszek <mknyszek@google.com>