cleanup(netx): another batch of small/simple cleanups (#789)

See https://github.com/ooni/probe/issues/2121

internal/netxlite/legacy.go

@@ -8,30 +8,19 @@ package netxlite
 //
 // Deprecated: do not use these names in new code.
 var (
-	DefaultDialer        = &DialerSystem{}
-	DefaultTLSHandshaker = defaultTLSHandshaker
-	NewResolverSystem    = newResolverSystem
-	NewConnUTLS          = newConnUTLS
-	DefaultResolver      = newResolverSystem()
+	DefaultDialer     = &DialerSystem{}
+	NewResolverSystem = newResolverSystem
+	DefaultResolver   = newResolverSystem()
 )
 
 // These types export internal names to legacy ooni/probe-cli code.
 //
 // Deprecated: do not use these names in new code.
 type (
-	DialerResolver                 = dialerResolver
-	DialerLogger                   = dialerLogger
 	HTTPTransportWrapper           = httpTransportConnectionsCloser
 	HTTPTransportLogger            = httpTransportLogger
-	ErrorWrapperDialer             = dialerErrWrapper
-	ErrorWrapperQUICListener       = quicListenerErrWrapper
-	ErrorWrapperQUICDialer         = quicDialerErrWrapper
 	ErrorWrapperResolver           = resolverErrWrapper
 	ErrorWrapperTLSHandshaker      = tlsHandshakerErrWrapper
-	QUICListenerStdlib             = quicListenerStdlib
-	QUICDialerQUICGo               = quicDialerQUICGo
-	QUICDialerResolver             = quicDialerResolver
-	QUICDialerLogger               = quicDialerLogger
 	ResolverSystemDoNotInstantiate = resolverSystem // instantiate => crash w/ nil transport
 	ResolverLogger                 = resolverLogger
 	ResolverIDNA                   = resolverIDNA

internal/netxlite/tls.go

@@ -215,9 +215,6 @@ func (h *tlsHandshakerConfigurable) newConn(conn net.Conn, config *tls.Config) (
 	return tls.Client(conn, config), nil
 }
 
-// defaultTLSHandshaker is the default TLS handshaker.
-var defaultTLSHandshaker = &tlsHandshakerConfigurable{}
-
 // tlsHandshakerLogger is a TLSHandshaker with logging.
 type tlsHandshakerLogger struct {
 	TLSHandshaker model.TLSHandshaker