cmd/go: resolve std-vendored dependencies as std packages except in 'go get' and 'go mod'
In CL 251159, I removed a hard-coded special case changing the
rewriting behavior for std dependencies in GOROOT/src/vendor and
GOROOT/src/cmd/vendor. Unfortunately, that caused packages in 'std' to
be reported as stale when run within GOROOT/src.
This change restores the special-case behavior, but plumbs it through
the PackageOpts explicitly instead of comparing strings stored in
global variables.
Fixes #44725
Change-Id: If084fe74972ce1704715ca79b0b7e092dd90c88b
Reviewed-on: https://go-review.googlesource.com/c/go/+/297869
Trust: Bryan C. Mills <bcmills@google.com>
Run-TryBot: Bryan C. Mills <bcmills@google.com>
TryBot-Result: Go Bot <gobot@golang.org> Reviewed-by: Jay Conrod <jayconrod@google.com>