Implement fetching, caching and retrieval of external policy data

chrome/browser/policy/cloud/cloud_external_data_manager.cc

 // Copyright 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.
 
 #include "chrome/browser/policy/cloud/cloud_external_data_manager.h"
 
+#include "chrome/browser/policy/cloud/cloud_policy_store.h"
+#include "net/url_request/url_request_context_getter.h"
+
 namespace policy {
 
 CloudExternalDataManager::MetadataEntry::MetadataEntry() {
 }
 
 CloudExternalDataManager::MetadataEntry::MetadataEntry(const std::string& url,
                                                        const std::string& hash)
     : url(url),
       hash(hash) {
 }
 
+bool CloudExternalDataManager::MetadataEntry::operator!=(
+    const MetadataEntry& other) const {
+  return url != other.url || hash != other.hash;
+}
+
+CloudExternalDataManager::CloudExternalDataManager() : policy_store_(NULL),
+                                                       weak_factory_(this) {
+}
+
+CloudExternalDataManager::~CloudExternalDataManager() {
+}
+
+void CloudExternalDataManager::SetPolicyStore(CloudPolicyStore* policy_store) {
+  policy_store_ = policy_store;
+  if (policy_store_)
+    policy_store_->SetExternalDataManager(weak_factory_.GetWeakPtr());
+}
+
 }  // namespace policy