PolicyDomainDescriptor must be RefCountedThreadSafe.

chrome/browser/policy/policy_domain_descriptor.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_POLICY_DOMAIN_DESCRIPTOR_H_
 #define CHROME_BROWSER_POLICY_POLICY_DOMAIN_DESCRIPTOR_H_
 
 #include <map>
 #include <string>
 
 #include "base/basictypes.h"
 #include "base/memory/ref_counted.h"
 #include "base/memory/scoped_ptr.h"
 #include "chrome/browser/policy/policy_service.h"
 
 namespace policy {
 
 class PolicyBundle;
 class PolicySchema;
 
 // For each policy domain, this class keeps the complete list of valid
 // components for that domain, and the PolicySchema for each component.
-class PolicyDomainDescriptor : public base::RefCounted<PolicyDomainDescriptor> {
+class PolicyDomainDescriptor
+    : public base::RefCountedThreadSafe<PolicyDomainDescriptor> {
  public:
   typedef std::map<std::string, const PolicySchema*> SchemaMap;
 
   explicit PolicyDomainDescriptor(PolicyDomain domain);
 
   PolicyDomain domain() const { return domain_; }
   const SchemaMap& components() const { return schema_map_; }
 
   // Registers the given |component_id| for this domain, and sets its current
   // |schema|. This registration overrides any previously set schema for this
   // component.
   void RegisterComponent(const std::string& component_id,
                          scoped_ptr<PolicySchema> schema);
 
   // Removes all the policies in |bundle| that don't match this descriptor.
   // Policies of domains other than |domain_| are ignored.
   void FilterBundle(PolicyBundle* bundle) const;
 
  private:
-  friend class base::RefCounted<PolicyDomainDescriptor>;
+  friend class base::RefCountedThreadSafe<PolicyDomainDescriptor>;
   ~PolicyDomainDescriptor();
 
   PolicyDomain domain_;
   SchemaMap schema_map_;
 
   DISALLOW_COPY_AND_ASSIGN(PolicyDomainDescriptor);
 };
 
 }  // namespace policy
 
 #endif  // CHROME_BROWSER_POLICY_POLICY_DOMAIN_DESCRIPTOR_H_