Use std::unique_ptr for base::DictionaryValue and base::ListValue's internal store.

chrome/browser/metrics/plugin_metrics_provider.cc

 // Copyright 2014 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/metrics/plugin_metrics_provider.h"
 
 #include <stddef.h>
 
 #include <string>
 
@@ skipping 123 matching lines @@
 void PluginMetricsProvider::ProvideStabilityMetrics(
     metrics::SystemProfileProto* system_profile_proto) {
   RecordCurrentStateIfPending();
   const base::ListValue* plugin_stats_list = local_state_->GetList(
       prefs::kStabilityPluginStats);
   if (!plugin_stats_list)
     return;
 
   metrics::SystemProfileProto::Stability* stability =
       system_profile_proto->mutable_stability();
-  for (base::ListValue::const_iterator iter = plugin_stats_list->begin();
-       iter != plugin_stats_list->end(); ++iter) {
-    if (!(*iter)->IsType(base::Value::TYPE_DICTIONARY)) {
+  for (const auto& value : *plugin_stats_list) {
+    base::DictionaryValue* plugin_dict;
+    if (!value->GetAsDictionary(&plugin_dict)) {
       NOTREACHED();
       continue;
     }
-    base::DictionaryValue* plugin_dict =
-        static_cast<base::DictionaryValue*>(*iter);
 
     // Note that this search is potentially a quadratic operation, but given the
     // low number of plugins installed on a "reasonable" setup, this should be
     // fine.
     // TODO(isherman): Verify that this does not show up as a hotspot in
     // profiler runs.
     const metrics::SystemProfileProto::Plugin* system_profile_plugin = NULL;
     std::string plugin_name;
     plugin_dict->GetString(prefs::kStabilityPluginName, &plugin_name);
     for (int i = 0; i < system_profile_proto->plugin_size(); ++i) {
@@ skipping 41 matching lines @@
   local_state_->ClearPref(prefs::kStabilityPluginStats);
 }
 
 // Saves plugin-related updates from the in-object buffer to Local State
 // for retrieval next time we send a Profile log (generally next launch).
 void PluginMetricsProvider::RecordCurrentState() {
   ListPrefUpdate update(local_state_, prefs::kStabilityPluginStats);
   base::ListValue* plugins = update.Get();
   DCHECK(plugins);
 
-  for (base::ListValue::iterator value_iter = plugins->begin();
-       value_iter != plugins->end(); ++value_iter) {
-    if (!(*value_iter)->IsType(base::Value::TYPE_DICTIONARY)) {
+  for (const auto& value : *plugins) {
+    base::DictionaryValue* plugin_dict;
+    if (!value->GetAsDictionary(&plugin_dict)) {
       NOTREACHED();
       continue;
     }
 
-    base::DictionaryValue* plugin_dict =
-        static_cast<base::DictionaryValue*>(*value_iter);
     base::string16 plugin_name;
     plugin_dict->GetString(prefs::kStabilityPluginName, &plugin_name);
     if (plugin_name.empty()) {
       NOTREACHED();
       continue;
     }
 
     if (child_process_stats_buffer_.find(plugin_name) ==
         child_process_stats_buffer_.end()) {
       continue;
@@ skipping 146 matching lines @@
 }
 
 bool PluginMetricsProvider::RecordCurrentStateIfPending() {
   if (!weak_ptr_factory_.HasWeakPtrs())
     return false;
 
   weak_ptr_factory_.InvalidateWeakPtrs();
   RecordCurrentState();
   return true;
 }