[net/dns] Serve requests from HOSTS file if possible.

net/dns/dns_test_util.h

 // Copyright (c) 2012 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.
 
 #ifndef NET_DNS_DNS_TEST_UTIL_H_
 #define NET_DNS_DNS_TEST_UTIL_H_
 #pragma once
 
 #include "base/basictypes.h"
+#include "base/memory/scoped_ptr.h"
+#include "net/dns/dns_config_service.h"
 #include "net/dns/dns_protocol.h"
 
 namespace net {
 
 //-----------------------------------------------------------------------------
 // Query/response set for www.google.com, ID is fixed to 0.
 static const char kT0HostName[] = "www.google.com";
 static const uint16 kT0Qtype = dns_protocol::kTypeA;
 static const char kT0DnsName[] = {
   0x03, 'w', 'w', 'w',
@@ skipping 129 matching lines @@
   0x47, 0x00, 0x01, 0x00, 0x01, 0x00, 0x00, 0x00,
   0x15, 0x00, 0x04, 0x4a, 0x7d, 0xe2, 0xb1
 };
 static const char* const kT3IpAddresses[] = {
   "74.125.226.178", "74.125.226.179", "74.125.226.180",
   "74.125.226.176", "74.125.226.177"
 };
 static const char kT3CanonName[] = "www.l.google.com";
 static const int kT3TTL = 0x00000015;
 
+class DnsClient;
+// Creates mock DnsClient for testing HostResolverImpl.
+scoped_ptr<DnsClient> CreateMockDnsClient(const DnsConfig& config);
+
+class MockDnsConfigService : public DnsConfigService {
+ public:
+  virtual ~MockDnsConfigService() {}
+
+  // Expose the protected methods for tests.
+  void ChangeConfig(const DnsConfig& config) {
+    DnsConfigService::OnConfigRead(config);
+  }
+
+  void ChangeHosts(const DnsHosts& hosts) {
+    DnsConfigService::OnHostsRead(hosts);
+  }
+};
+
+
 }  // namespace net
 
 #endif  // NET_DNS_DNS_TEST_UTIL_H_