api: remove os.File.Size and http.Transport.Dialer
api: remove os.File.Size and http.Transport.Dialer

This method and field were added and then later removed during the 1.7
development cycle.

Change-Id: I0482a6356b91d2be67880b44ef5d8a1daab49ec8
Reviewed-on: https://go-review.googlesource.com/23670
Reviewed-by: Chris Broadfoot <0c2851a4f8ab4aa5606e69c0757771dd13dbe686@golang.org>

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