Got error:
'go' is not an internal or external command, nor is it a runnable program

Change-Id: Ie45a3a12252fa01b67ca09ef8fbb5b4bbf728fe7
GitHub-Last-Rev: 451815cacd9bfc509fa0aab3be54303797e605a2
GitHub-Pull-Request: golang/go#27214
Reviewed-on: https://go-review.googlesource.com/131397Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>