Extend VariationParamsManager to support feature associations.

components/ntp_snippets/remote/ntp_snippets_status_service.h

 // Copyright 2016 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 COMPONENTS_NTP_SNIPPETS_REMOTE_NTP_SNIPPETS_STATUS_SERVICE_H_
 #define COMPONENTS_NTP_SNIPPETS_REMOTE_NTP_SNIPPETS_STATUS_SERVICE_H_
 
 #include "base/callback.h"
 #include "base/gtest_prod_util.h"
 #include "base/scoped_observer.h"
@@ skipping 34 matching lines @@
   // Starts listening for changes from the dependencies. |callback| will be
   // called when a significant change in state is detected.
   void Init(const SnippetsStatusChangeCallback& callback);
 
   // To be called when the signin state changed. Will compute the new
   // state considering the initialisation configuration and the preferences,
   // and notify via the registered callback if appropriate.
   void OnSignInStateChanged();
 
  private:
+  FRIEND_TEST_ALL_PREFIXES(NTPSnippetsStatusServiceTest,
+                           SigninStateCompatibility);
   FRIEND_TEST_ALL_PREFIXES(NTPSnippetsStatusServiceTest, DisabledViaPref);
 
   // Callback for the PrefChangeRegistrar.
   void OnSnippetsEnabledChanged();
 
   void OnStateChanged(SnippetsStatus new_snippets_status);
 
   bool IsSignedIn() const;
 
   SnippetsStatus GetSnippetsStatusFromDeps() const;
 
   SnippetsStatus snippets_status_;
   SnippetsStatusChangeCallback snippets_status_change_callback_;
 
   bool require_signin_;
   SigninManagerBase* signin_manager_;
   PrefService* pref_service_;
 
   PrefChangeRegistrar pref_change_registrar_;
 
   DISALLOW_COPY_AND_ASSIGN(NTPSnippetsStatusService);
 };
 
 }  // namespace ntp_snippets
 
 #endif  // COMPONENTS_NTP_SNIPPETS_REMOTE_NTP_SNIPPETS_STATUS_SERVICE_H_