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diff --git a/chromium/net/dns/dns_config_service.h b/chromium/net/dns/dns_config_service.h
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index 00000000000..4babb9e7d37
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+++ b/chromium/net/dns/dns_config_service.h
@@ -0,0 +1,174 @@
+// 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_CONFIG_SERVICE_H_
+#define NET_DNS_DNS_CONFIG_SERVICE_H_
+
+#include <map>
+#include <string>
+#include <vector>
+
+#include "base/gtest_prod_util.h"
+#include "base/memory/scoped_ptr.h"
+#include "base/threading/non_thread_safe.h"
+#include "base/time/time.h"
+#include "base/timer/timer.h"
+// Needed on shared build with MSVS2010 to avoid multiple definitions of
+// std::vector<IPEndPoint>.
+#include "net/base/address_list.h"
+#include "net/base/ip_endpoint.h"  // win requires size of IPEndPoint
+#include "net/base/net_export.h"
+#include "net/dns/dns_hosts.h"
+
+namespace base {
+class Value;
+}
+
+namespace net {
+
+// Always use 1 second timeout (followed by binary exponential backoff).
+// TODO(szym): Remove code which reads timeout from system.
+const unsigned kDnsTimeoutSeconds = 1;
+
+// DnsConfig stores configuration of the system resolver.
+struct NET_EXPORT_PRIVATE DnsConfig {
+  DnsConfig();
+  virtual ~DnsConfig();
+
+  bool Equals(const DnsConfig& d) const;
+
+  bool EqualsIgnoreHosts(const DnsConfig& d) const;
+
+  void CopyIgnoreHosts(const DnsConfig& src);
+
+  // Returns a Value representation of |this|.  Caller takes ownership of the
+  // returned Value.  For performance reasons, the Value only contains the
+  // number of hosts rather than the full list.
+  base::Value* ToValue() const;
+
+  bool IsValid() const {
+    return !nameservers.empty();
+  }
+
+  // List of name server addresses.
+  std::vector<IPEndPoint> nameservers;
+  // Suffix search list; used on first lookup when number of dots in given name
+  // is less than |ndots|.
+  std::vector<std::string> search;
+
+  DnsHosts hosts;
+
+  // AppendToMultiLabelName: is suffix search performed for multi-label names?
+  // True, except on Windows where it can be configured.
+  bool append_to_multi_label_name;
+
+  // Indicates that source port randomization is required. This uses additional
+  // resources on some platforms.
+  bool randomize_ports;
+
+  // Resolver options; see man resolv.conf.
+
+  // Minimum number of dots before global resolution precedes |search|.
+  int ndots;
+  // Time between retransmissions, see res_state.retrans.
+  base::TimeDelta timeout;
+  // Maximum number of attempts, see res_state.retry.
+  int attempts;
+  // Round robin entries in |nameservers| for subsequent requests.
+  bool rotate;
+  // Enable EDNS0 extensions.
+  bool edns0;
+};
+
+
+// Service for reading system DNS settings, on demand or when signalled by
+// internal watchers and NetworkChangeNotifier.
+class NET_EXPORT_PRIVATE DnsConfigService
+    : NON_EXPORTED_BASE(public base::NonThreadSafe) {
+ public:
+  // Callback interface for the client, called on the same thread as
+  // ReadConfig() and WatchConfig().
+  typedef base::Callback<void(const DnsConfig& config)> CallbackType;
+
+  // Creates the platform-specific DnsConfigService.
+  static scoped_ptr<DnsConfigService> CreateSystemService();
+
+  DnsConfigService();
+  virtual ~DnsConfigService();
+
+  // Attempts to read the configuration. Will run |callback| when succeeded.
+  // Can be called at most once.
+  void ReadConfig(const CallbackType& callback);
+
+  // Registers systems watchers. Will attempt to read config after watch starts,
+  // but only if watchers started successfully. Will run |callback| iff config
+  // changes from last call or has to be withdrawn. Can be called at most once.
+  // Might require MessageLoopForIO.
+  void WatchConfig(const CallbackType& callback);
+
+ protected:
+  enum WatchStatus {
+    DNS_CONFIG_WATCH_STARTED = 0,
+    DNS_CONFIG_WATCH_FAILED_TO_START_CONFIG,
+    DNS_CONFIG_WATCH_FAILED_TO_START_HOSTS,
+    DNS_CONFIG_WATCH_FAILED_CONFIG,
+    DNS_CONFIG_WATCH_FAILED_HOSTS,
+    DNS_CONFIG_WATCH_MAX,
+  };
+
+ // Immediately attempts to read the current configuration.
+  virtual void ReadNow() = 0;
+  // Registers system watchers. Returns true iff succeeds.
+  virtual bool StartWatching() = 0;
+
+  // Called when the current config (except hosts) has changed.
+  void InvalidateConfig();
+  // Called when the current hosts have changed.
+  void InvalidateHosts();
+
+  // Called with new config. |config|.hosts is ignored.
+  void OnConfigRead(const DnsConfig& config);
+  // Called with new hosts. Rest of the config is assumed unchanged.
+  void OnHostsRead(const DnsHosts& hosts);
+
+  void set_watch_failed(bool value) { watch_failed_ = value; }
+
+ private:
+  // The timer counts from the last Invalidate* until complete config is read.
+  void StartTimer();
+  void OnTimeout();
+  // Called when the config becomes complete. Stops the timer.
+  void OnCompleteConfig();
+
+  CallbackType callback_;
+
+  DnsConfig dns_config_;
+
+  // True if any of the necessary watchers failed. In that case, the service
+  // will communicate changes via OnTimeout, but will only send empty DnsConfig.
+  bool watch_failed_;
+  // True after On*Read, before Invalidate*. Tells if the config is complete.
+  bool have_config_;
+  bool have_hosts_;
+  // True if receiver needs to be updated when the config becomes complete.
+  bool need_update_;
+  // True if the last config sent was empty (instead of |dns_config_|).
+  // Set when |timer_| expires.
+  bool last_sent_empty_;
+
+  // Initialized and updated on Invalidate* call.
+  base::TimeTicks last_invalidate_config_time_;
+  base::TimeTicks last_invalidate_hosts_time_;
+  // Initialized and updated when |timer_| expires.
+  base::TimeTicks last_sent_empty_time_;
+
+  // Started in Invalidate*, cleared in On*Read.
+  base::OneShotTimer<DnsConfigService> timer_;
+
+  DISALLOW_COPY_AND_ASSIGN(DnsConfigService);
+};
+
+}  // namespace net
+
+#endif  // NET_DNS_DNS_CONFIG_SERVICE_H_