Uses mojom module names as Dart's package: import URI

mojo/services/http_server/public/interfaces/http_request.mojom

 // Copyright 2014 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.
 
+[DartUriBase="mojo/services/http_server/public/interfaces"]
 module http_server;
 
 struct HttpRequest {
   string relative_url;  // Starts with '/'. Example: "/test?query=foo"
 
   // The HTTP method if applicable.
   string method = "GET";
 
   // Additional HTTP request headers.
   map<string, string>? headers;
 
   // The payload for the request body. Only set for "POST" or "PUT".
   handle<data_pipe_consumer>? body;
 };