net/http: remove unused ResponseWriter params
net/http: remove unused ResponseWriter params

Found by github.com/mvdan/unparam.

Change-Id: I66f5a191cf9c9a11a7c3c4d7ee0a02e2c185f019
Reviewed-on: https://go-review.googlesource.com/37841
Reviewed-by: Brad Fitzpatrick <ae9783c0b0efc69cd85ab025ddd17aa44cdc4aa5@golang.org>
Run-TryBot: Brad Fitzpatrick <ae9783c0b0efc69cd85ab025ddd17aa44cdc4aa5@golang.org>

polyverse-security/go,CAFxX/go,akutz/go,CAFxX/go,josharian/go,golang/go,vsekhar/elastic-go,derekmarcotte/go,derekmarcotte/go,josharian/go,derekmarcotte/go,cloudflare/go,CAFxX/go,polyverse-security/go,codestation/go,codestation/go,derekmarcotte/go,ImJasonH/go,akutz/go,Cofyc/go,derekmarcotte/go,golang/go,akutz/go,golang/go,akutz/go,golang/go,ImJasonH/go,codestation/go,Cofyc/go,cloudflare/go,akutz/go,codestation/go,nawawi/go,polyverse-security/go,Cofyc/go,golang/go,CAFxX/go,derekmarcotte/go,polyverse-security/go,ImJasonH/go,vsekhar/elastic-go,nawawi/go,golang/go,linux-on-ibm-z/go,josharian/go,ImJasonH/go,linux-on-ibm-z/go,vsekhar/elastic-go,ImJasonH/go,codestation/go,vsekhar/elastic-go,josharian/go,polyverse-security/go,polyverse-security/go,josharian/go,CAFxX/go,vsekhar/elastic-go,cloudflare/go,cloudflare/go,Cofyc/go,codestation/go,polyverse-security/go,derekmarcotte/go,Cofyc/go,linux-on-ibm-z/go,nawawi/go,akutz/go,derekmarcotte/go,josharian/go,linux-on-ibm-z/go,nawawi/go,ImJasonH/go,vsekhar/elastic-go,golang/go,linux-on-ibm-z/go,vsekhar/elastic-go,cloudflare/go,codestation/go,CAFxX/go,polyverse-security/go,Cofyc/go,josharian/go,nawawi/go,linux-on-ibm-z/go,linux-on-ibm-z/go,cloudflare/go,cloudflare/go,Cofyc/go,josharian/go,codestation/go,cloudflare/go,CAFxX/go,ImJasonH/go,ImJasonH/go,nawawi/go,akutz/go,golang/go,linux-on-ibm-z/go,akutz/go,nawawi/go,Cofyc/go,christopher-henderson/Go,nawawi/go,vsekhar/elastic-go,CAFxX/go