Provide and respect HTTP cache headers in pub serve.

test/serve/utils.dart

 // Copyright (c) 2013, the Dart project authors.  Please see the AUTHORS d.file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 import 'dart:async';
 import 'dart:convert';
 import 'dart:io';
 
 import 'package:http/http.dart' as http;
 import 'package:pub/src/utils.dart';
@@ skipping 213 matching lines @@
 }
 
 void endPubServe() {
   _pubServer.kill();
 }
 
 /// Schedules an HTTP request to the running pub server with [urlPath] and
 /// invokes [callback] with the response.
 ///
 /// [root] indicates which server should be accessed, and defaults to "web".
-Future<http.Response> scheduleRequest(String urlPath, {String root}) {
+Future<http.Response> scheduleRequest(String urlPath,
+    {String root, Map<String, String> headers}) {
   return schedule(() {
-    return http.get(_getServerUrlSync(root, urlPath));
+    return http.get(_getServerUrlSync(root, urlPath), headers: headers);
   }, "request $urlPath");
 }
 
 /// Schedules an HTTP request to the running pub server with [urlPath] and
 /// verifies that it responds with a body that matches [expectation].
 ///
 /// [expectation] may either be a [Matcher] or a string to match an exact body.
 /// [root] indicates which server should be accessed, and defaults to "web".
 /// [headers] may be either a [Matcher] or a map to match an exact headers map.
 void requestShouldSucceed(String urlPath, expectation, {String root, headers}) {
@@ skipping 229 matching lines @@
 /// included. Unlike [getServerUrl], this should only be called after the ports
 /// are known.
 String _getServerUrlSync([String root, String path]) {
   if (root == null) root = 'web';
   expect(_ports, contains(root));
   var url = "http://localhost:${_ports[root]}";
   if (path != null) url = "$url/$path";
   return url;
 }