ComponentCloudPolicyService tracks the signin state.

chrome/browser/policy/cloud/resource_cache.h

 // Copyright (c) 2013 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 CHROME_BROWSER_POLICY_CLOUD_RESOURCE_CACHE_H_
 #define CHROME_BROWSER_POLICY_CLOUD_RESOURCE_CACHE_H_
 
 #include <map>
 #include <set>
 #include <string>
@@ skipping 34 matching lines @@
             const std::string& subkey,
             std::string* data);
 
   // Loads all the subkeys of |key| into |contents|.
   void LoadAllSubkeys(const std::string& key,
                       std::map<std::string, std::string>* contents);
 
   // Deletes (key, subkey).
   void Delete(const std::string& key, const std::string& subkey);
 
+  // Deletes all the subkeys of |key|.
+  void Clear(const std::string& key);
+
   // Deletes the subkeys of |key| for which the |filter| returns true.
   typedef base::Callback<bool(const std::string&)> SubkeyFilter;
   void FilterSubkeys(const std::string& key, const SubkeyFilter& filter);
 
   // Deletes all keys not in |keys_to_keep|, along with their subkeys.
   void PurgeOtherKeys(const std::set<std::string>& keys_to_keep);
 
   // Deletes all the subkeys of |key| not in |subkeys_to_keep|.
   void PurgeOtherSubkeys(const std::string& key,
                          const std::set<std::string>& subkeys_to_keep);
@@ skipping 19 matching lines @@
 
   // Task runner that |this| runs on.
   scoped_refptr<base::SequencedTaskRunner> task_runner_;
 
   DISALLOW_COPY_AND_ASSIGN(ResourceCache);
 };
 
 }  // namespace policy
 
 #endif  // CHROME_BROWSER_POLICY_CLOUD_RESOURCE_CACHE_H_