Add browser tests for clearing sync registrations with site data

content/browser/background_sync/background_sync_network_observer.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 CONTENT_BROWSER_BACKGROUND_SYNC_BACKGROUND_SYNC_NETWORK_OBSERVER_H_
 #define CONTENT_BROWSER_BACKGROUND_SYNC_BACKGROUND_SYNC_NETWORK_OBSERVER_H_
 
 #include "base/bind.h"
 #include "content/browser/background_sync/background_sync.pb.h"
 #include "content/common/content_export.h"
@@ skipping 15 matching lines @@
   static void SetIgnoreNetworkChangeNotifierForTests(bool ignore);
 
   // Returns true if the state of the network meets the needs of
   // |network_state|.
   bool NetworkSufficient(SyncNetworkState network_state);
 
   // NetworkChangeObserver overrides
   void OnNetworkChanged(
       net::NetworkChangeNotifier::ConnectionType connection_type) override;
 
+  // Allow tests to call NotifyManagerIfNetworkChanged.
+  void NotifyManagerIfNetworkChangedForTesting(
+      net::NetworkChangeNotifier::ConnectionType connection_type);
+
  private:
-  friend class BackgroundSyncBrowserTest;
-  friend class BackgroundSyncManagerTest;
-  friend class BackgroundSyncServiceImplTest;
-
   // Calls NotifyNetworkChanged if the connection type has changed.
   void NotifyManagerIfNetworkChanged(
       net::NetworkChangeNotifier::ConnectionType connection_type);
 
   void NotifyNetworkChanged();
 
   net::NetworkChangeNotifier::ConnectionType connection_type_;
 
   // The callback to run when the network changes.
   base::Closure network_changed_callback_;
 
   // Set true to ignore notifications coming from the NetworkChangeNotifier
   // (to prevent flakes in tests).
   static bool ignore_network_change_notifier_;
 
   DISALLOW_COPY_AND_ASSIGN(BackgroundSyncNetworkObserver);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_BROWSER_BACKGROUND_SYNC_BACKGROUND_SYNC_NETWORK_OBSERVER_H_