cmd/compile: document parsing decision for imported interfaces
cmd/compile: document parsing decision for imported interfaces

Fixes #13245.

Change-Id: I87be63cc7b27f70ca2f9fb6bc9908b9061fe3d9d
Reviewed-on: https://go-review.googlesource.com/17203
Reviewed-by: Chris Manghane <fe04d2e6759ff872548dffaa0000d96c00597e75@golang.org>

Cofyc/go,kim-racktop/go,goodlang/good,cyberroadie/go,roth1002/go,derekmarcotte/go,derekmarcotte/go,binarycrusader/go,miolini/go,odeke-em/go,kim-racktop/go,cyberroadie/go,goodlang/good,momchil-velikov/go,Endika/go,miolini/go,linux-on-ibm-z/go,ganboing/go-esx,fjballest/golang,suncycheng/go,polyverse-security/go,sndnvaps/go,suncycheng/go,polyverse-security/go,ganboing/go-esx,miolini/go,momchil-velikov/go,cloudflare/go,polyverse-security/go,theif519/go,sndnvaps/go,josharian/go,golang/go,Samurais/go,polyverse-security/go,ImJasonH/go,derekmarcotte/go,CAFxX/go,ImJasonH/go,suncycheng/go,binarycrusader/go,cloudflare/go,derekmarcotte/go,nawawi/go,momchil-velikov/go,derekmarcotte/go,deft-code/go,CAFxX/go,polyverse-security/go,akutz/go,binarycrusader/go,cyberroadie/go,polyverse-security/go,4ad/go,linux-on-ibm-z/go,cloudflare/go,fjballest/golang,miolini/go,theif519/go,akutz/go,deft-code/go,vanloswang/go,binarycrusader/go,momchil-velikov/go,cyberroadie/go,odeke-em/go,fjballest/golang,goodlang/good,cloudflare/go,odeke-em/go,cloudflare/go,golang/go,nawawi/go,4ad/go,Samurais/go,odeke-em/go,sndnvaps/go,nawawi/go,kim-racktop/go,4ad/go,polyverse-security/go,CAFxX/go,roth1002/go,goodlang/good,Cofyc/go,ganboing/go-esx,vsekhar/elastic-go,vanloswang/go,josharian/go,derekmarcotte/go,cyberroadie/go,CAFxX/go,odeke-em/go,suncycheng/go,vanloswang/go,ImJasonH/go,cloudflare/go,vanloswang/go,roth1002/go,4ad/go,mwhudson/go,sndnvaps/go,linux-on-ibm-z/go,ImJasonH/go,derekmarcotte/go,linux-on-ibm-z/go,vanloswang/go,fjballest/golang,CAFxX/go,deft-code/go,ganboing/go-esx,odeke-em/go,mwhudson/go,linux-on-ibm-z/go,binarycrusader/go,Cofyc/go,mwhudson/go,christopher-henderson/Go,4ad/go,suncycheng/go,kim-racktop/go,ganboing/go-esx,Samurais/go,CAFxX/go,4ad/go,vsekhar/elastic-go,vsekhar/elastic-go,Cofyc/go,linux-on-ibm-z/go,Cofyc/go,cyberroadie/go,suncycheng/go,ganboing/go-esx,codestation/go,CAFxX/go,suncycheng/go,roth1002/go,codestation/go,sndnvaps/go,josharian/go,miolini/go,golang/go,roth1002/go,josharian/go,Endika/go,ImJasonH/go,codestation/go,deft-code/go,ganboing/go-esx,golang/go,Samurais/go,kim-racktop/go,fjballest/golang,nawawi/go,vanloswang/go,miolini/go,Cofyc/go,ganboing/go-esx,binarycrusader/go,Endika/go,momchil-velikov/go,theif519/go,nawawi/go,nawawi/go,roth1002/go,ImJasonH/go,akutz/go,ImJasonH/go,josharian/go,goodlang/good,ImJasonH/go,kim-racktop/go,momchil-velikov/go,Samurais/go,akutz/go,sndnvaps/go,vsekhar/elastic-go,suncycheng/go,Samurais/go,Endika/go,miolini/go,odeke-em/go,Endika/go,josharian/go,miolini/go,vsekhar/elastic-go,roth1002/go,Cofyc/go,mwhudson/go,theif519/go,mwhudson/go,derekmarcotte/go,Endika/go,nawawi/go,deft-code/go,cyberroadie/go,deft-code/go,vsekhar/elastic-go,golang/go,vanloswang/go,goodlang/good,fjballest/golang,codestation/go,Samurais/go,4ad/go,codestation/go,josharian/go,akutz/go,linux-on-ibm-z/go,akutz/go,mwhudson/go,vsekhar/elastic-go,mwhudson/go,akutz/go,deft-code/go,vsekhar/elastic-go,CAFxX/go,linux-on-ibm-z/go,sndnvaps/go,cloudflare/go,Samurais/go,goodlang/good,theif519/go,Endika/go,kim-racktop/go,goodlang/good,theif519/go,polyverse-security/go,mwhudson/go,momchil-velikov/go,nawawi/go,4ad/go,codestation/go,binarycrusader/go,cloudflare/go,vanloswang/go,golang/go,cyberroadie/go,sndnvaps/go,kim-racktop/go,codestation/go,golang/go,momchil-velikov/go,fjballest/golang,codestation/go,fjballest/golang,deft-code/go,theif519/go,binarycrusader/go,odeke-em/go,Cofyc/go,akutz/go,roth1002/go,theif519/go,golang/go,josharian/go,Endika/go