Revert 202478 "Revert 202388 "Remove NetworkStateInformer's depe..."

trunk/src/chromeos/network/managed_state.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 CHROMEOS_NETWORK_MANAGED_STATE_H_
 #define CHROMEOS_NETWORK_MANAGED_STATE_H_
 
 #include <string>
 
 #include "base/basictypes.h"
@@ skipping 22 matching lines @@
 
   // This will construct and return a new instance of the appropriate class
   // based on |type|.
   static ManagedState* Create(ManagedType type, const std::string& path);
 
   // Returns the specific class pointer if this is the correct type, or
   // NULL if it is not.
   NetworkState* AsNetworkState();
   DeviceState* AsDeviceState();
 
-  // Called by NetworkStateHandler when a property changes. Returns false if
-  // the property was not recognized, was not parsed successfully, or is
-  // unchanged (complex properties may be assumed to have changed).
+  // Called by NetworkStateHandler when a property was received. The return
+  // value indicates if the state changed and is used to reduce the number of
+  // notifications. The only guarantee however is: If the return value is false
+  // then the state wasn't modified. This might happen because of
+  // * |key| was not recognized.
+  // * |value| was not parsed successfully.
+  // * |value| is equal to the cached property value.
+  // If the return value is true, the state might or might not be modified.
   virtual bool PropertyChanged(const std::string& key,
                                const base::Value& value) = 0;
 
   // Called by NetworkStateHandler after all calls to PropertyChanged for the
   // initial set of properties. Used to update state requiring multiple
   // parsed properties, e.g. name from hex_ssid in NetworkState.
   virtual void InitialPropertiesReceived();
 
   const ManagedType managed_type() const { return managed_type_; }
   const std::string& path() const { return path_; }
@@ skipping 44 matching lines @@
 
   // Tracks when an update has been requested.
   bool update_requested_;
 
   DISALLOW_COPY_AND_ASSIGN(ManagedState);
 };
 
 }  // namespace chromeos
 
 #endif  // CHROMEOS_NETWORK_MANAGED_STATE_H_