Remove unused context.Domain

it was added (and wrong idx) on previous commit for some of my internal
tests, this is not used anywhere so remove it.

context.go

@@ -297,15 +297,6 @@ func (ctx *Context) PostFormMulti(name string) []string {
 	return arrStr
 }
 
-// Domain same as VirtualHostname but without the :port part (if any)
-func (ctx *Context) Domain() string {
-	domain := ctx.VirtualHostname()
-	if idx := strings.IndexByte(domain, ':'); idx > 0 {
-		domain = domain[0 : idx-1]
-	}
-	return domain
-}
-
 // Subdomain returns the subdomain (string) of this request, if any
 func (ctx *Context) Subdomain() (subdomain string) {
 	host := ctx.HostString()

context/context.go

@@ -23,7 +23,6 @@ type (
 		URLParams() map[string]string
 		MethodString() string
 		HostString() string
-		Domain() string
 		Subdomain() string
 		PathString() string
 		RequestPath(bool) string

sessions/manager.go

@@ -94,7 +94,7 @@ func (m *Manager) Start(ctx context.IContext) store.IStore {
 		cookie.SetValue(base64.URLEncoding.EncodeToString([]byte(sid)))
 		cookie.SetPath("/")
 		if !m.config.DisableSubdomainPersistance {
-			requestDomain := ctx.HostString() // we don't use the ctx.Domain because it gives the virtual domain, which is correct on some cases but not here.
+			requestDomain := ctx.HostString()
 
 			if portIdx := strings.IndexByte(requestDomain, ':'); portIdx > 0 {
 				requestDomain = requestDomain[0:portIdx]