Require an explicit ServiceName annotation for interfaces in C++.

mojo/services/http_server/interfaces/http_server_factory.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.
 
 [DartPackage="mojo_services"]
 module http_server;
 
 import "http_server/interfaces/http_server.mojom";
 import "network/interfaces/net_address.mojom";
 
+[ServiceName="http_server::HttpServerFactory"]
 interface HttpServerFactory {
   // Creates an http server running on the specified local network address.  If
   // |local_address| is null, it will take the default value of 0.0.0.0 at a
   // system-allocated port.
   //
   // Note that the port value of 0 means that the operating system will pick
   // one of available ports. You can use HttpServer::GetPort() to retrieve the
   // allocated port.
   //
   // Only one backing server will be created for each local network address. It
   // will be shared among clients, if more than one client requests a server
   // running on a particular network address.
   //
   // TODO(ppi): would it be better to create a server only for the first caller
   // and require the access to it to be explicitly shared by the party that
   // requests it first?
   CreateHttpServer(HttpServer& server_request, mojo.NetAddress? local_address);
 };