test: add test for issue 15602
test: add test for issue 15602

The problem was fixed by the rollback in CL 22930.
This CL just adds a test to prevent regressions.

Fixes #15602

Change-Id: I37453f6e18ca43081266fe7f154c6d63fbaffd9b
Reviewed-on: https://go-review.googlesource.com/22931
Run-TryBot: Josh Bleecher Snyder <cdc248cc4d32e4fbfe04e45228163bcecd48a0b9@gmail.com>
TryBot-Result: Gobot Gobot <66cb808b70d30c07676d5e946fee83fd561249e5@golang.org>
Reviewed-by: Matthew Dempsky <e56ac2c500064424afac424d4b5e53bd0570a731@google.com>

vsekhar/elastic-go,ImJasonH/go,momchil-velikov/go,vsekhar/elastic-go,ganboing/go-esx,nawawi/go,ganboing/go-esx,theif519/go,goodlang/good,polyverse-security/go,vsekhar/elastic-go,4ad/go,Cofyc/go,theif519/go,codestation/go,linux-on-ibm-z/go,nawawi/go,ImJasonH/go,vsekhar/elastic-go,cloudflare/go,Cofyc/go,christopher-henderson/Go,polyverse-security/go,momchil-velikov/go,theif519/go,momchil-velikov/go,codestation/go,CAFxX/go,ImJasonH/go,Cofyc/go,codestation/go,theif519/go,golang/go,golang/go,akutz/go,akutz/go,cloudflare/go,codestation/go,theif519/go,suncycheng/go,ganboing/go-esx,goodlang/good,nawawi/go,vsekhar/elastic-go,Cofyc/go,suncycheng/go,vsekhar/elastic-go,akutz/go,CAFxX/go,momchil-velikov/go,CAFxX/go,derekmarcotte/go,suncycheng/go,linux-on-ibm-z/go,derekmarcotte/go,josharian/go,4ad/go,suncycheng/go,Cofyc/go,josharian/go,ganboing/go-esx,ImJasonH/go,vsekhar/elastic-go,nawawi/go,ImJasonH/go,codestation/go,golang/go,derekmarcotte/go,polyverse-security/go,linux-on-ibm-z/go,golang/go,goodlang/good,codestation/go,goodlang/good,cloudflare/go,momchil-velikov/go,momchil-velikov/go,Cofyc/go,linux-on-ibm-z/go,4ad/go,linux-on-ibm-z/go,CAFxX/go,josharian/go,ImJasonH/go,theif519/go,golang/go,cloudflare/go,ImJasonH/go,CAFxX/go,josharian/go,suncycheng/go,akutz/go,vsekhar/elastic-go,suncycheng/go,josharian/go,4ad/go,suncycheng/go,nawawi/go,linux-on-ibm-z/go,cloudflare/go,4ad/go,akutz/go,josharian/go,Cofyc/go,momchil-velikov/go,theif519/go,4ad/go,akutz/go,Cofyc/go,polyverse-security/go,CAFxX/go,theif519/go,CAFxX/go,golang/go,ganboing/go-esx,nawawi/go,CAFxX/go,nawawi/go,polyverse-security/go,golang/go,josharian/go,ganboing/go-esx,akutz/go,ImJasonH/go,codestation/go,golang/go,goodlang/good,cloudflare/go,suncycheng/go,derekmarcotte/go,polyverse-security/go,ganboing/go-esx,momchil-velikov/go,derekmarcotte/go,cloudflare/go,cloudflare/go,goodlang/good,linux-on-ibm-z/go,goodlang/good,akutz/go,ganboing/go-esx,codestation/go,4ad/go,derekmarcotte/go,goodlang/good,derekmarcotte/go,nawawi/go,polyverse-security/go,derekmarcotte/go,josharian/go,linux-on-ibm-z/go,4ad/go,polyverse-security/go