Remove base::ScopedPtrHashMap from components/policy/.

components/policy/core/common/policy_namespace.h

 // 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.
 
 #ifndef COMPONENTS_POLICY_CORE_COMMON_POLICY_NAMESPACE_H_
 #define COMPONENTS_POLICY_CORE_COMMON_POLICY_NAMESPACE_H_
 
 #include <stddef.h>
 #include <stdint.h>
 
@@ skipping 36 matching lines @@
   bool operator<(const PolicyNamespace& other) const;
   bool operator==(const PolicyNamespace& other) const;
   bool operator!=(const PolicyNamespace& other) const;
 
   PolicyDomain domain;
   std::string component_id;
 };
 
 typedef std::vector<PolicyNamespace> PolicyNamespaceList;
 
-}  // namespace policy
-
-// Define a custom std::hash for PolicyNamespace so that it can be used as
-// a key in hash_maps, and in particular in ScopedPtrHashMaps (which uses the
-// default std::hash).
-namespace BASE_HASH_NAMESPACE {
-
-template <>
-struct hash<policy::PolicyNamespace> {
-  std::size_t operator()(const policy::PolicyNamespace& ns) const {
-    return hash<std::string>()(ns.component_id) ^ (UINT64_C(1) << ns.domain);
+struct PolicyNamespaceHash {
+  size_t operator()(const policy::PolicyNamespace& ns) const {
+    return std::hash<std::string>()(ns.component_id) ^
+           (UINT64_C(1) << ns.domain);
   }
 };
 
-}  // namespace BASE_HASH_NAMESPACE
+}  // namespace policy
 
 #endif  // COMPONENTS_POLICY_CORE_COMMON_POLICY_NAMESPACE_H_