language: add Go test data in standard form

 generated from data_test.go

The generation code is transitional and will
be removed with the next change.

Change-Id: I50e0a91e9d3a5e7cede617714619a3b7be031b8c
Reviewed-on: https://go-review.googlesource.com/55390
Run-TryBot: Marcel van Lohuizen <mpvl@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Nigel Tao <nigeltao@golang.org>