Use std::unique_ptr to express ownership of base::Value in PolicyMap::Entry

remoting/host/policy_watcher.cc

 // Copyright 2015 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.
 
 // Most of this code is copied from:
 //   src/chrome/browser/policy/asynchronous_policy_loader.{h,cc}
 
 #include "remoting/host/policy_watcher.h"
 
 #include <utility>
@@ skipping 72 matching lines @@
       new policy::SchemaRegistry());
   schema_registry->RegisterComponent(GetPolicyNamespace(), schema);
   return schema_registry;
 }
 
 std::unique_ptr<base::DictionaryValue> CopyChromotingPoliciesIntoDictionary(
     const policy::PolicyMap& current) {
   const char kPolicyNameSubstring[] = "RemoteAccessHost";
   std::unique_ptr<base::DictionaryValue> policy_dict(
       new base::DictionaryValue());
-  for (auto it = current.begin(); it != current.end(); ++it) {
-    const std::string& key = it->first;
-    const base::Value* value = it->second.value;
+  for (const auto& entry : current) {
+    const std::string& key = entry.first;
+    const base::Value* value = entry.second.value.get();
 
     // Copying only Chromoting-specific policies helps avoid false alarms
     // raised by NormalizePolicies below (such alarms shutdown the host).
     // TODO(lukasza): Removing this somewhat brittle filtering will be possible
     //                after having separate, Chromoting-specific schema.
     if (key.find(kPolicyNameSubstring) != std::string::npos) {
       policy_dict->Set(key, value->CreateDeepCopy());
     }
   }
 
@@ skipping 276 matching lines @@
       CreateSchemaRegistry()));
 #else
 #error OS that is not yet supported by PolicyWatcher code.
 #endif
 
   return PolicyWatcher::CreateFromPolicyLoader(std::move(policy_loader));
 #endif  // !(OS_CHROMEOS)
 }
 
 }  // namespace remoting