Reland: Add test for system tray network menu icon for extension-controlled networks

ash/common/system/networking_config_delegate.h

 // Copyright 2015 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 ASH_COMMON_SYSTEM_NETWORKING_CONFIG_DELEGATE_H_
 #define ASH_COMMON_SYSTEM_NETWORKING_CONFIG_DELEGATE_H_
 
 #include <memory>
 #include <string>
 
 #include "ash/ash_export.h"
 #include "base/macros.h"
 
 namespace ash {
 
 // This delegate allows the UI code in ash, e.g. |NetworkStateListDetailedView|,
 // to access the |NetworkingConfigService| in order to determine whether the
 // configuration of a network identified by its |service_path| is controlled by
 // an extension.
+// TODO(crbug.com/651157): Eliminate this delegate. Information about extension
+// controlled networks should be provided by a mojo service that caches data at
+// the NetworkState level.
 class NetworkingConfigDelegate {
  public:
   // A struct that provides information about the extension controlling the
   // configuration of a network.
   struct ASH_EXPORT ExtensionInfo {
     ExtensionInfo(const std::string& id, const std::string& name);
     ~ExtensionInfo();
     std::string extension_id;
     std::string extension_name;
   };
 
   virtual ~NetworkingConfigDelegate() {}
 
   // Returns information about the extension registered to control configuration
   // of the network |service_path|. Returns null if no extension is registered.
   virtual std::unique_ptr<const ExtensionInfo> LookUpExtensionForNetwork(
       const std::string& service_path) = 0;
 
  private:
   DISALLOW_ASSIGN(NetworkingConfigDelegate);
 };
 
 }  // namespace ash
 
 #endif  // ASH_COMMON_SYSTEM_NETWORKING_CONFIG_DELEGATE_H_