Make sure to alloc+copy large keys and values instead of aliasing them,
when they might be updated by a future assignment.
Fixes #64474
Change-Id: Ie2226a81cf3897e4e2ee24472f2966d397ace53f
Reviewed-on: https://go-review.googlesource.com/c/go/+/546515 Reviewed-by: Cherry Mui <cherryyz@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com> Reviewed-by: Keith Randall <khr@google.com> Reviewed-by: Mauri de Souza Meneguzzo <mauri870@gmail.com>