cmd/api: bump go.tools golden CL hash

TBR=bradfitz
R=rsc
CC=golang-codereviews
https://codereview.appspot.com/166380043
undo CL 166380043 / 0b54a0927656

This was a mistake; the cmd/api tool
depends on an old version of go/types.

««« original CL description
cmd/api: bump go.tools golden CL hash

TBR=bradfitz
R=rsc
CC=golang-codereviews
https://codereview.appspot.com/166380043
»»»

TBR=bradfitz, rsc
R=bradfitz, rsc
CC=golang-codereviews
https://codereview.appspot.com/167430043