Replace //net TypeConverters with StructTraits.

net/interfaces/proxy_resolver_service.mojom

 // Copyright 2015 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 // Put Mojo definitions into their own namespace to avoid collisions with C++
 // definitions.
 // TODO(amistry): Resolve the conflict between these two sets of definitions.
 module net.interfaces;
 
 import "host_resolver_service.mojom";
 import "url/mojo/url.mojom";
 
 // Mirror of net::ProxyServer::Scheme.
 enum ProxyScheme {
   INVALID,
   DIRECT,
   HTTP,
   SOCKS4,
   SOCKS5,
   HTTPS,
   QUIC,
 };
 
 // Mirror of net::ProxyServer.
 struct ProxyServer {
   ProxyScheme scheme;
 
   // |host| and |port| are only valid if |scheme| is not INVALID or DIRECT.
-  string? host;
+  string host;
   uint16 port;
 };
 
+struct ProxyInfo {
+  array<ProxyServer> proxy_servers;
+};
+
 interface ProxyResolver {
   // Use a ProxyResolverRequestClient instead of returning a result so we can
   // cancel in-flight requests by destroying the client.
   GetProxyForUrl(url.mojom.Url url, ProxyResolverRequestClient client);
 };
 
 interface ProxyResolverRequestClient {
-  ReportResult(int32 error, array<ProxyServer>? proxy_servers);
+  ReportResult(int32 error, ProxyInfo proxy_info);
 
   Alert(string error);
   OnError(int32 line_number, string error);
 
   ResolveDns(HostResolverRequestInfo request_info,
              HostResolverRequestClient client);
 };
 
 interface ProxyResolverFactory {
   CreateResolver(string pac_script,
                  ProxyResolver& resolver,
                  ProxyResolverFactoryRequestClient client);
 };
 
 interface ProxyResolverFactoryRequestClient {
   ReportResult(int32 error);
 
   Alert(string error);
   OnError(int32 line_number, string error);
 
   ResolveDns(HostResolverRequestInfo request_info,
              HostResolverRequestClient client);
 };