Tests commonly use code to get os.Executable value, and some cache the
resulting value.
To reduce code duplication, add a helper that does just that.
Change-Id: I9dd7eb24e24a3abd92be2b87227e823f0fca5cb3
Reviewed-on: https://go-review.googlesource.com/c/go/+/609301 Reviewed-by: Cherry Mui <cherryyz@google.com> Reviewed-by: Ian Lance Taylor <iant@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com> Reviewed-by: Alan Donovan <adonovan@google.com>
Auto-Submit: Ian Lance Taylor <iant@google.com>