cmd/go: fail go clean command when failed to find go cache directory
Currently, if computing of the go cache directory fails it does not expose the error. Commands like go clean, exec, modindex that use go cache directory continue execution producing incorrect or no result. This patch adds an error to the return values such that it can be validated on call sites. It also introduces such validation in go clean -cache command to fail execution in case when error occurred.
Fixes #69997
Change-Id: I53fd1ec67f0a6bd8a367e785dcb145a673c084dc
GitHub-Last-Rev:
e2063d10db7bb969bcbc8993761e3b38bb420938
GitHub-Pull-Request: golang/go#70392
Reviewed-on: https://go-review.googlesource.com/c/go/+/628596
Reviewed-by: Michael Matloob <matloob@golang.org>
Reviewed-by: Cherry Mui <cherryyz@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Auto-Submit: Michael Matloob <matloob@golang.org>