Refactored the CloudPolicyProvider so that it becomes initialized once and stays initialized.

chrome/browser/policy/cloud_policy_provider_impl.h

-// Copyright (c) 2012 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_POLICY_PROVIDER_IMPL_H_
-#define CHROME_BROWSER_POLICY_CLOUD_POLICY_PROVIDER_IMPL_H_
-#pragma once
-
-#include <vector>
-
-#include "chrome/browser/policy/cloud_policy_cache_base.h"
-#include "chrome/browser/policy/cloud_policy_provider.h"
-#include "chrome/browser/policy/policy_map.h"
-
-namespace policy {
-
-class BrowserPolicyConnector;
-
-class CloudPolicyProviderImpl : public CloudPolicyProvider,
-                                public CloudPolicyCacheBase::Observer {
- public:
-  CloudPolicyProviderImpl(BrowserPolicyConnector* browser_policy_connector,
-                          const PolicyDefinitionList* policy_list,
-                          PolicyLevel level);
-  virtual ~CloudPolicyProviderImpl();
-
-  // ConfigurationPolicyProvider implementation.
-  virtual bool ProvideInternal(PolicyMap* result) OVERRIDE;
-  virtual bool IsInitializationComplete() const OVERRIDE;
-  virtual void RefreshPolicies() OVERRIDE;
-
-  // CloudPolicyCacheBase::Observer implementation.
-  virtual void OnCacheUpdate(CloudPolicyCacheBase* cache) OVERRIDE;
-  virtual void OnCacheGoingAway(CloudPolicyCacheBase* cache) OVERRIDE;
-  virtual void AppendCache(CloudPolicyCacheBase* cache) OVERRIDE;
-  virtual void PrependCache(CloudPolicyCacheBase* cache) OVERRIDE;
-
- private:
-  friend class CloudPolicyProviderTest;
-
-  typedef std::vector<CloudPolicyCacheBase*> ListType;
-
-  // Recompute |combined_| from |caches_| and trigger an OnUpdatePolicy if
-  // something changed. This is called whenever a change in one of the caches
-  // is observed. For i=0..n-1: |caches_[i]| will contribute all its policies
-  // except those already provided by |caches_[0]|..|caches_[i-1]|.
-  void RecombineCachesAndTriggerUpdate();
-
-  // Removes |cache| from |caches|, if contained therein.
-  static void RemoveCache(CloudPolicyCacheBase* cache, ListType* caches);
-
-  // Weak pointer to the connector. Guaranteed to outlive |this|.
-  BrowserPolicyConnector* browser_policy_connector_;
-
-  // The underlying policy caches.
-  ListType caches_;
-
-  // Caches with pending updates. Used by RefreshPolicies to determine if a
-  // refresh has fully completed.
-  ListType pending_update_caches_;
-
-  // Policy level this provider will handle.
-  PolicyLevel level_;
-
-  // Whether all caches are fully initialized.
-  bool initialization_complete_;
-
-  // The currently valid combination of all the maps in |caches_|. Will be
-  // applied as is on call of Provide.
-  PolicyMap combined_;
-
-  DISALLOW_COPY_AND_ASSIGN(CloudPolicyProviderImpl);
-};
-
-}  // namespace policy
-
-#endif  // CHROME_BROWSER_POLICY_CLOUD_POLICY_PROVIDER_IMPL_H_