base: Add AsList() function to Value API.

This function should simplify some constructions.

Instead of:

if (!value->IsType(Value::TYPE_LIST))
  return false;
ListValue* list_value = static_cast<ListValue*>(value);

You can do:

ListValue* list_value = value->AsList();
if (!list_value)
  return false;

BUG=None
TEST=base_unittests --gtest_filter=Values*

R=evan@chromium.org,tony@chromium.org

Review URL: http://codereview.chromium.org/7714004

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@98223 0039d316-1c4b-4281-b951-d872f2087c98

29 files changed, 226 insertions, 205 deletions

diff --git a/base/json/json_reader_unittest.cc b/base/json/json_reader_unittest.cc
index a7aeaf0..7623a68 100644
--- a/base/json/json_reader_unittest.cc
+++ b/base/json/json_reader_unittest.cc
@@ -222,8 +222,8 @@ TEST(JSONReaderTest, Reading) {
   // Basic array
   root.reset(JSONReader::Read("[true, false, null]", false));
   ASSERT_TRUE(root.get());
-  ASSERT_TRUE(root->IsType(Value::TYPE_LIST));
-  ListValue* list = static_cast<ListValue*>(root.get());
+  ListValue* list = root->AsList();
+  ASSERT_TRUE(list);
   ASSERT_EQ(3U, list->GetSize());
 
   // Test with trailing comma.  Should be parsed the same as above.
@@ -234,16 +234,16 @@ TEST(JSONReaderTest, Reading) {
   // Empty array
   root.reset(JSONReader::Read("[]", false));
   ASSERT_TRUE(root.get());
-  ASSERT_TRUE(root->IsType(Value::TYPE_LIST));
-  list = static_cast<ListValue*>(root.get());
+  list = root->AsList();
+  ASSERT_TRUE(list);
   ASSERT_EQ(0U, list->GetSize());
 
   // Nested arrays
   root.reset(JSONReader::Read("[[true], [], [false, [], [null]], null]",
                               false));
   ASSERT_TRUE(root.get());
-  ASSERT_TRUE(root->IsType(Value::TYPE_LIST));
-  list = static_cast<ListValue*>(root.get());
+  list = root->AsList();
+  ASSERT_TRUE(list);
   ASSERT_EQ(4U, list->GetSize());
 
   // Lots of trailing commas.
@@ -272,8 +272,8 @@ TEST(JSONReaderTest, Reading) {
   // Valid if we set |allow_trailing_comma| to true.
   root.reset(JSONReader::Read("[true,]", true));
   ASSERT_TRUE(root.get());
-  ASSERT_TRUE(root->IsType(Value::TYPE_LIST));
-  list = static_cast<ListValue*>(root.get());
+  list = root->AsList();
+  ASSERT_TRUE(list);
   EXPECT_EQ(1U, list->GetSize());
   Value* tmp_value = NULL;
   ASSERT_TRUE(list->Get(0, &tmp_value));
@@ -435,8 +435,8 @@ TEST(JSONReaderTest, Reading) {
   not_evil.append("[]]");
   root.reset(JSONReader::Read(not_evil, false));
   ASSERT_TRUE(root.get());
-  ASSERT_TRUE(root->IsType(Value::TYPE_LIST));
-  list = static_cast<ListValue*>(root.get());
+  list = root->AsList();
+  ASSERT_TRUE(list);
   ASSERT_EQ(5001U, list->GetSize());
 
   // Test utf8 encoded input
diff --git a/base/values.cc b/base/values.cc
index 17aba16..1798695 100644
--- a/base/values.cc
+++ b/base/values.cc
@@ -97,6 +97,10 @@ StringValue* Value::CreateStringValue(const string16& in_value) {
   return new StringValue(in_value);
 }
 
+ListValue* Value::AsList() {
+  return NULL;
+}
+
 bool Value::GetAsBoolean(bool* out_value) const {
   return false;
 }
@@ -511,7 +515,7 @@ bool DictionaryValue::GetList(const std::string& path,
                               ListValue** out_value) const {
   Value* value;
   bool result = Get(path, &value);
-  if (!result || !value->IsType(TYPE_LIST))
+  if (!result || !value->AsList())
     return false;
 
   if (out_value)
@@ -589,7 +593,7 @@ bool DictionaryValue::GetListWithoutPathExpansion(const std::string& key,
                                                   ListValue** out_value) const {
   Value* value;
   bool result = GetWithoutPathExpansion(key, &value);
-  if (!result || !value->IsType(TYPE_LIST))
+  if (!result || !value->AsList())
     return false;
 
   if (out_value)
@@ -802,7 +806,7 @@ bool ListValue::GetDictionary(size_t index, DictionaryValue** out_value) const {
 bool ListValue::GetList(size_t index, ListValue** out_value) const {
   Value* value;
   bool result = Get(index, &value);
-  if (!result || !value->IsType(TYPE_LIST))
+  if (!result || !value->AsList())
     return false;
 
   if (out_value)
@@ -865,6 +869,10 @@ bool ListValue::Insert(size_t index, Value* in_value) {
   return true;
 }
 
+ListValue* ListValue::AsList() {
+  return this;
+}
+
 bool ListValue::GetAsList(ListValue** out_value) {
   if (out_value)
     *out_value = this;
diff --git a/base/values.h b/base/values.h
index a30791b..2f41215 100644
--- a/base/values.h
+++ b/base/values.h
@@ -87,6 +87,8 @@ class BASE_EXPORT Value {
   // Returns true if the current object represents a given type.
   bool IsType(Type type) const { return type == type_; }
 
+  virtual ListValue* AsList();
+
   // These methods allow the convenient retrieval of settings.
   // If the current setting object can be converted into the given type,
   // the value is returned through the |out_value| parameter and true is
@@ -431,6 +433,7 @@ class BASE_EXPORT ListValue : public Value {
   const_iterator end() const { return list_.end(); }
 
   // Overridden from Value:
+  virtual ListValue* AsList() OVERRIDE;
   virtual bool GetAsList(ListValue** out_value) OVERRIDE;
   virtual bool GetAsList(const ListValue** out_value) const OVERRIDE;
   virtual ListValue* DeepCopy() const OVERRIDE;
diff --git a/base/values_unittest.cc b/base/values_unittest.cc
index 553e8e1..c8d3e3c 100644
--- a/base/values_unittest.cc
+++ b/base/values_unittest.cc
@@ -429,8 +429,8 @@ TEST(ValuesTest, DeepCopy) {
   ASSERT_TRUE(copy_dict->Get("list", &copy_value));
   ASSERT_TRUE(copy_value);
   ASSERT_NE(copy_value, original_list);
-  ASSERT_TRUE(copy_value->IsType(Value::TYPE_LIST));
-  ListValue* copy_list = static_cast<ListValue*>(copy_value);
+  ListValue* copy_list = copy_value->AsList();
+  ASSERT_TRUE(copy_list != NULL);
   ASSERT_EQ(2U, copy_list->GetSize());
 
   Value* copy_list_element_0;
diff --git a/chrome/browser/autocomplete/search_provider.cc b/chrome/browser/autocomplete/search_provider.cc
index 1dae40a..8bd3478 100644
--- a/chrome/browser/autocomplete/search_provider.cc
+++ b/chrome/browser/autocomplete/search_provider.cc
@@ -452,9 +452,9 @@ bool SearchProvider::ParseSuggestResults(Value* root_val,
                                          bool is_keyword,
                                          const string16& input_text,
                                          SuggestResults* suggest_results) {
-  if (!root_val->IsType(Value::TYPE_LIST))
+  ListValue* root_list = root_val->AsList();
+  if (!root_list)
     return false;
-  ListValue* root_list = static_cast<ListValue*>(root_val);
 
   Value* query_val;
   string16 query_str;
@@ -462,16 +462,15 @@ bool SearchProvider::ParseSuggestResults(Value* root_val,
   if ((root_list->GetSize() < 2) || !root_list->Get(0, &query_val) ||
       !query_val->GetAsString(&query_str) ||
       (query_str != input_text) ||
-      !root_list->Get(1, &result_val) || !result_val->IsType(Value::TYPE_LIST))
+      !root_list->Get(1, &result_val) || !result_val->AsList())
     return false;
 
   ListValue* description_list = NULL;
   if (root_list->GetSize() > 2) {
     // 3rd element: Description list.
     Value* description_val;
-    if (root_list->Get(2, &description_val) &&
-        description_val->IsType(Value::TYPE_LIST))
-      description_list = static_cast<ListValue*>(description_val);
+    if (root_list->Get(2, &description_val))
+      description_list = description_val->AsList();
   }
 
   // We don't care about the query URL list (the fourth element in the
diff --git a/chrome/browser/chromeos/cros/native_network_parser.cc b/chrome/browser/chromeos/cros/native_network_parser.cc
index 3172025..24340b2 100644
--- a/chrome/browser/chromeos/cros/native_network_parser.cc
+++ b/chrome/browser/chromeos/cros/native_network_parser.cc
@@ -147,12 +147,13 @@ NativeNetworkDeviceParser::NativeNetworkDeviceParser()
 NativeNetworkDeviceParser::~NativeNetworkDeviceParser() {
 }
 
-bool NativeNetworkDeviceParser::ParseValue(
-    PropertyIndex index, const Value& value, NetworkDevice* device) {
+bool NativeNetworkDeviceParser::ParseValue(PropertyIndex index,
+                                           Value* value,
+                                           NetworkDevice* device) {
   switch (index) {
     case PROPERTY_INDEX_TYPE: {
       std::string type_string;
-      if (value.GetAsString(&type_string)) {
+      if (value->GetAsString(&type_string)) {
         device->set_type(ParseType(type_string));
         return true;
       }
@@ -160,79 +161,75 @@ bool NativeNetworkDeviceParser::ParseValue(
     }
     case PROPERTY_INDEX_NAME: {
       std::string name;
-      if (!value.GetAsString(&name))
+      if (!value->GetAsString(&name))
         return false;
       device->set_name(name);
       return true;
     }
     case PROPERTY_INDEX_GUID: {
       std::string unique_id;
-      if (!value.GetAsString(&unique_id))
+      if (!value->GetAsString(&unique_id))
         return false;
       device->set_unique_id(unique_id);
       return true;
     }
     case PROPERTY_INDEX_CARRIER: {
       std::string carrier;
-      if (!value.GetAsString(&carrier))
+      if (!value->GetAsString(&carrier))
         return false;
       device->set_carrier(carrier);
       return true;
     }
     case PROPERTY_INDEX_SCANNING: {
       bool scanning;
-      if (!value.GetAsBoolean(&scanning))
+      if (!value->GetAsBoolean(&scanning))
         return false;
       device->set_scanning(scanning);
       return true;
     }
     case PROPERTY_INDEX_CELLULAR_ALLOW_ROAMING: {
       bool data_roaming_allowed;
-      if (!value.GetAsBoolean(&data_roaming_allowed))
+      if (!value->GetAsBoolean(&data_roaming_allowed))
         return false;
       device->set_data_roaming_allowed(data_roaming_allowed);
       return true;
     }
     case PROPERTY_INDEX_CELLULAR_APN_LIST:
-      if (value.IsType(Value::TYPE_LIST)) {
+      if (ListValue* list = value->AsList()) {
         CellularApnList provider_apn_list;
-        if (!ParseApnList(static_cast<const ListValue&>(value),
-                          &provider_apn_list))
+        if (!ParseApnList(*list, &provider_apn_list))
           return false;
         device->set_provider_apn_list(provider_apn_list);
         return true;
       }
       break;
     case PROPERTY_INDEX_NETWORKS:
-      if (value.IsType(Value::TYPE_LIST)) {
+      if (value->AsList()) {
         // Ignored.
         return true;
       }
       break;
     case PROPERTY_INDEX_FOUND_NETWORKS:
-      if (value.IsType(Value::TYPE_LIST)) {
+      if (ListValue* list = value->AsList()) {
         CellularNetworkList found_cellular_networks;
-        if (!ParseFoundNetworksFromList(
-                static_cast<const ListValue&>(value),
-                &found_cellular_networks))
+        if (!ParseFoundNetworksFromList(*list, &found_cellular_networks))
           return false;
         device->set_found_cellular_networks(found_cellular_networks);
         return true;
       }
       break;
     case PROPERTY_INDEX_HOME_PROVIDER: {
-      if (value.IsType(Value::TYPE_DICTIONARY)) {
-        const DictionaryValue& dict =
-            static_cast<const DictionaryValue&>(value);
+      if (value->IsType(Value::TYPE_DICTIONARY)) {
+        DictionaryValue* dict = static_cast<DictionaryValue*>(value);
         std::string home_provider_code;
         std::string home_provider_country;
         std::string home_provider_name;
-        dict.GetStringWithoutPathExpansion(kOperatorCodeKey,
-                                           &home_provider_code);
-        dict.GetStringWithoutPathExpansion(kOperatorCountryKey,
-                                           &home_provider_country);
-        dict.GetStringWithoutPathExpansion(kOperatorNameKey,
-                                           &home_provider_name);
+        dict->GetStringWithoutPathExpansion(kOperatorCodeKey,
+                                            &home_provider_code);
+        dict->GetStringWithoutPathExpansion(kOperatorCountryKey,
+                                            &home_provider_country);
+        dict->GetStringWithoutPathExpansion(kOperatorNameKey,
+                                            &home_provider_name);
         device->set_home_provider_code(home_provider_code);
         device->set_home_provider_country(home_provider_country);
         device->set_home_provider_name(home_provider_name);
@@ -263,7 +260,7 @@ bool NativeNetworkDeviceParser::ParseValue(
     case PROPERTY_INDEX_HARDWARE_REVISION:
     case PROPERTY_INDEX_SELECTED_NETWORK: {
       std::string item;
-      if (!value.GetAsString(&item))
+      if (!value->GetAsString(&item))
         return false;
       switch (index) {
         case PROPERTY_INDEX_MEID:
@@ -305,11 +302,11 @@ bool NativeNetworkDeviceParser::ParseValue(
       return true;
     }
     case PROPERTY_INDEX_SIM_LOCK:
-      if (value.IsType(Value::TYPE_DICTIONARY)) {
+      if (value->IsType(Value::TYPE_DICTIONARY)) {
         SimLockState sim_lock_state;
         int sim_retries_left;
         if (!ParseSimLockStateFromDictionary(
-                static_cast<const DictionaryValue&>(value),
+                static_cast<const DictionaryValue&>(*value),
                 &sim_lock_state,
                 &sim_retries_left))
           return false;
@@ -333,21 +330,21 @@ bool NativeNetworkDeviceParser::ParseValue(
       return true;
     case PROPERTY_INDEX_PRL_VERSION: {
       int prl_version;
-      if (!value.GetAsInteger(&prl_version))
+      if (!value->GetAsInteger(&prl_version))
         return false;
       device->set_prl_version(prl_version);
       return true;
     }
     case PROPERTY_INDEX_SUPPORT_NETWORK_SCAN: {
       bool support_network_scan;
-      if (!value.GetAsBoolean(&support_network_scan))
+      if (!value->GetAsBoolean(&support_network_scan))
         return false;
       device->set_support_network_scan(support_network_scan);
       return true;
     }
     case PROPERTY_INDEX_TECHNOLOGY_FAMILY: {
       std::string technology_family_string;
-      if (value.GetAsString(&technology_family_string)) {
+      if (value->GetAsString(&technology_family_string)) {
         device->set_technology_family(
             ParseTechnologyFamily(technology_family_string));
         return true;
@@ -477,12 +474,12 @@ const ConnectionType NativeNetworkParser::ParseConnectionType(
 }
 
 bool NativeNetworkParser::ParseValue(PropertyIndex index,
-                                     const Value& value,
+                                     Value* value,
                                      Network* network) {
   switch (index) {
     case PROPERTY_INDEX_TYPE: {
       std::string type_string;
-      if (value.GetAsString(&type_string)) {
+      if (value->GetAsString(&type_string)) {
         ConnectionType type = ParseType(type_string);
         LOG_IF(ERROR, type != network->type())
           << "Network with mismatched type: " << network->service_path()
@@ -493,21 +490,21 @@ bool NativeNetworkParser::ParseValue(PropertyIndex index,
     }
     case PROPERTY_INDEX_DEVICE: {
       std::string device_path;
-      if (!value.GetAsString(&device_path))
+      if (!value->GetAsString(&device_path))
         return false;
       network->set_device_path(device_path);
       return true;
     }
     case PROPERTY_INDEX_NAME: {
       std::string name;
-      if (!value.GetAsString(&name))
+      if (!value->GetAsString(&name))
         return false;
       network->SetName(name);
       return true;
     }
     case PROPERTY_INDEX_GUID: {
       std::string unique_id;
-      if (!value.GetAsString(&unique_id))
+      if (!value->GetAsString(&unique_id))
         return false;
       network->set_unique_id(unique_id);
       return true;
@@ -515,14 +512,14 @@ bool NativeNetworkParser::ParseValue(PropertyIndex index,
     case PROPERTY_INDEX_PROFILE: {
       // Note: currently this is only provided for non remembered networks.
       std::string profile_path;
-      if (!value.GetAsString(&profile_path))
+      if (!value->GetAsString(&profile_path))
         return false;
       network->set_profile_path(profile_path);
       return true;
     }
     case PROPERTY_INDEX_STATE: {
       std::string state_string;
-      if (value.GetAsString(&state_string)) {
+      if (value->GetAsString(&state_string)) {
         network->SetState(ParseState(state_string));
         return true;
       }
@@ -530,7 +527,7 @@ bool NativeNetworkParser::ParseValue(PropertyIndex index,
     }
     case PROPERTY_INDEX_MODE: {
       std::string mode_string;
-      if (value.GetAsString(&mode_string)) {
+      if (value->GetAsString(&mode_string)) {
         network->set_mode(ParseMode(mode_string));
         return true;
       }
@@ -538,7 +535,7 @@ bool NativeNetworkParser::ParseValue(PropertyIndex index,
     }
     case PROPERTY_INDEX_ERROR: {
       std::string error_string;
-      if (value.GetAsString(&error_string)) {
+      if (value->GetAsString(&error_string)) {
         network->set_error(ParseError(error_string));
         return true;
       }
@@ -546,14 +543,14 @@ bool NativeNetworkParser::ParseValue(PropertyIndex index,
     }
     case PROPERTY_INDEX_CONNECTABLE: {
       bool connectable;
-      if (!value.GetAsBoolean(&connectable))
+      if (!value->GetAsBoolean(&connectable))
         return false;
       network->set_connectable(connectable);
       return true;
     }
     case PROPERTY_INDEX_IS_ACTIVE: {
       bool is_active;
-      if (!value.GetAsBoolean(&is_active))
+      if (!value->GetAsBoolean(&is_active))
         return false;
       network->set_is_active(is_active);
       return true;
@@ -563,21 +560,21 @@ bool NativeNetworkParser::ParseValue(PropertyIndex index,
       return true;
     case PROPERTY_INDEX_AUTO_CONNECT: {
       bool auto_connect;
-      if (!value.GetAsBoolean(&auto_connect))
+      if (!value->GetAsBoolean(&auto_connect))
         return false;
       network->set_auto_connect(auto_connect);
       return true;
     }
     case PROPERTY_INDEX_SAVE_CREDENTIALS: {
       bool save_credentials;
-      if (!value.GetAsBoolean(&save_credentials))
+      if (!value->GetAsBoolean(&save_credentials))
         return false;
       network->set_save_credentials(save_credentials);
       return true;
     }
     case PROPERTY_INDEX_PROXY_CONFIG: {
       std::string proxy_config;
-      if (!value.GetAsString(&proxy_config))
+      if (!value->GetAsString(&proxy_config))
         return false;
       network->set_proxy_config(proxy_config);
       return true;
@@ -660,7 +657,7 @@ NativeWirelessNetworkParser::NativeWirelessNetworkParser() {}
 NativeWirelessNetworkParser::~NativeWirelessNetworkParser() {}
 
 bool NativeWirelessNetworkParser::ParseValue(PropertyIndex index,
-                                             const Value& value,
+                                             Value* value,
                                              Network* network) {
   DCHECK_NE(TYPE_ETHERNET, network->type());
   DCHECK_NE(TYPE_VPN, network->type());
@@ -668,7 +665,7 @@ bool NativeWirelessNetworkParser::ParseValue(PropertyIndex index,
   switch (index) {
     case PROPERTY_INDEX_SIGNAL_STRENGTH: {
       int strength;
-      if (!value.GetAsInteger(&strength))
+      if (!value->GetAsInteger(&strength))
         return false;
       wireless_network->set_strength(strength);
       return true;
@@ -686,14 +683,14 @@ NativeCellularNetworkParser::NativeCellularNetworkParser() {}
 NativeCellularNetworkParser::~NativeCellularNetworkParser() {}
 
 bool NativeCellularNetworkParser::ParseValue(PropertyIndex index,
-                                             const Value& value,
+                                             Value* value,
                                              Network* network) {
   DCHECK_EQ(TYPE_CELLULAR, network->type());
   CellularNetwork* cellular_network = static_cast<CellularNetwork*>(network);
   switch (index) {
     case PROPERTY_INDEX_ACTIVATION_STATE: {
       std::string activation_state_string;
-      if (value.GetAsString(&activation_state_string)) {
+      if (value->GetAsString(&activation_state_string)) {
         ActivationState prev_state = cellular_network->activation_state();
         cellular_network->set_activation_state(
             ParseActivationState(activation_state_string));
@@ -704,23 +701,23 @@ bool NativeCellularNetworkParser::ParseValue(PropertyIndex index,
       break;
     }
     case PROPERTY_INDEX_CELLULAR_APN: {
-      if (value.IsType(Value::TYPE_DICTIONARY)) {
-        cellular_network->set_apn(static_cast<const DictionaryValue&>(value));
+      if (value->IsType(Value::TYPE_DICTIONARY)) {
+        cellular_network->set_apn(static_cast<const DictionaryValue&>(*value));
         return true;
       }
       break;
     }
     case PROPERTY_INDEX_CELLULAR_LAST_GOOD_APN: {
-      if (value.IsType(Value::TYPE_DICTIONARY)) {
+      if (value->IsType(Value::TYPE_DICTIONARY)) {
         cellular_network->set_last_good_apn(
-            static_cast<const DictionaryValue&>(value));
+            static_cast<const DictionaryValue&>(*value));
         return true;
       }
       break;
     }
     case PROPERTY_INDEX_NETWORK_TECHNOLOGY: {
       std::string network_technology_string;
-      if (value.GetAsString(&network_technology_string)) {
+      if (value->GetAsString(&network_technology_string)) {
         cellular_network->set_network_technology(
             ParseNetworkTechnology(network_technology_string));
         return true;
@@ -729,7 +726,7 @@ bool NativeCellularNetworkParser::ParseValue(PropertyIndex index,
     }
     case PROPERTY_INDEX_ROAMING_STATE: {
       std::string roaming_state_string;
-      if (value.GetAsString(&roaming_state_string)) {
+      if (value->GetAsString(&roaming_state_string)) {
         cellular_network->set_roaming_state(
             ParseRoamingState(roaming_state_string));
         return true;
@@ -738,22 +735,22 @@ bool NativeCellularNetworkParser::ParseValue(PropertyIndex index,
     }
     case PROPERTY_INDEX_OPERATOR_NAME: {
       std::string value_str;
-      if (!value.GetAsString(&value_str))
+      if (!value->GetAsString(&value_str))
         break;
       cellular_network->set_operator_name(value_str);
       return true;
     }
     case PROPERTY_INDEX_OPERATOR_CODE: {
       std::string value_str;
-      if (!value.GetAsString(&value_str))
+      if (!value->GetAsString(&value_str))
         break;
       cellular_network->set_operator_code(value_str);
       return true;
     }
     case PROPERTY_INDEX_SERVING_OPERATOR: {
-      if (value.IsType(Value::TYPE_DICTIONARY)) {
+      if (value->IsType(Value::TYPE_DICTIONARY)) {
         const DictionaryValue& dict =
-            static_cast<const DictionaryValue&>(value);
+            static_cast<const DictionaryValue&>(*value);
         std::string value_str;
         dict.GetStringWithoutPathExpansion(kOperatorNameKey, &value_str);
         cellular_network->set_operator_name(value_str);
@@ -769,14 +766,14 @@ bool NativeCellularNetworkParser::ParseValue(PropertyIndex index,
     }
     case PROPERTY_INDEX_PAYMENT_URL: {
       std::string value_str;
-      if (!value.GetAsString(&value_str))
+      if (!value->GetAsString(&value_str))
         break;
       cellular_network->set_payment_url(value_str);
       return true;
     }
     case PROPERTY_INDEX_USAGE_URL: {
       std::string value_str;
-      if (!value.GetAsString(&value_str))
+      if (!value->GetAsString(&value_str))
         break;
       cellular_network->set_usage_url(value_str);
       return true;
@@ -848,14 +845,14 @@ NativeWifiNetworkParser::NativeWifiNetworkParser() {}
 NativeWifiNetworkParser::~NativeWifiNetworkParser() {}
 
 bool NativeWifiNetworkParser::ParseValue(PropertyIndex index,
-                                         const Value& value,
+                                         Value* value,
                                          Network* network) {
   DCHECK_EQ(TYPE_WIFI, network->type());
   WifiNetwork* wifi_network = static_cast<WifiNetwork*>(network);
   switch (index) {
     case PROPERTY_INDEX_WIFI_HEX_SSID: {
       std::string ssid_hex;
-      if (!value.GetAsString(&ssid_hex))
+      if (!value->GetAsString(&ssid_hex))
         return false;
 
       wifi_network->SetHexSsid(ssid_hex);
@@ -876,21 +873,21 @@ bool NativeWifiNetworkParser::ParseValue(PropertyIndex index,
     }
     case PROPERTY_INDEX_GUID: {
       std::string unique_id;
-      if (!value.GetAsString(&unique_id))
+      if (!value->GetAsString(&unique_id))
         break;
       wifi_network->set_unique_id(unique_id);
       return true;
     }
     case PROPERTY_INDEX_SECURITY: {
       std::string security_string;
-      if (!value.GetAsString(&security_string))
+      if (!value->GetAsString(&security_string))
         break;
       wifi_network->set_encryption(ParseSecurity(security_string));
       return true;
     }
     case PROPERTY_INDEX_PASSPHRASE: {
       std::string passphrase;
-      if (!value.GetAsString(&passphrase))
+      if (!value->GetAsString(&passphrase))
         break;
       // Only store the passphrase if we are the owner.
       // TODO(stevenjb): Remove this when chromium-os:12948 is resolved.
@@ -900,57 +897,57 @@ bool NativeWifiNetworkParser::ParseValue(PropertyIndex index,
     }
     case PROPERTY_INDEX_PASSPHRASE_REQUIRED: {
       bool passphrase_required;
-      value.GetAsBoolean(&passphrase_required);
-      if (!value.GetAsBoolean(&passphrase_required))
+      value->GetAsBoolean(&passphrase_required);
+      if (!value->GetAsBoolean(&passphrase_required))
         break;
       wifi_network->set_passphrase_required(passphrase_required);
       return true;
     }
     case PROPERTY_INDEX_IDENTITY: {
       std::string identity;
-      if (!value.GetAsString(&identity))
+      if (!value->GetAsString(&identity))
         break;
       wifi_network->set_identity(identity);
       return true;
     }
     case PROPERTY_INDEX_EAP_IDENTITY: {
       std::string eap_identity;
-      if (!value.GetAsString(&eap_identity))
+      if (!value->GetAsString(&eap_identity))
         break;
       wifi_network->set_eap_identity(eap_identity);
       return true;
     }
     case PROPERTY_INDEX_EAP_METHOD: {
       std::string eap_method;
-      if (!value.GetAsString(&eap_method))
+      if (!value->GetAsString(&eap_method))
         break;
       wifi_network->set_eap_method(ParseEAPMethod(eap_method));
       return true;
     }
     case PROPERTY_INDEX_EAP_PHASE_2_AUTH: {
       std::string eap_phase_2_auth;
-      if (!value.GetAsString(&eap_phase_2_auth))
+      if (!value->GetAsString(&eap_phase_2_auth))
         break;
       wifi_network->set_eap_phase_2_auth(ParseEAPPhase2Auth(eap_phase_2_auth));
       return true;
     }
     case PROPERTY_INDEX_EAP_ANONYMOUS_IDENTITY: {
       std::string eap_anonymous_identity;
-      if (!value.GetAsString(&eap_anonymous_identity))
+      if (!value->GetAsString(&eap_anonymous_identity))
         break;
       wifi_network->set_eap_anonymous_identity(eap_anonymous_identity);
       return true;
     }
     case PROPERTY_INDEX_EAP_CERT_ID: {
       std::string eap_client_cert_pkcs11_id;
-      if (!value.GetAsString(&eap_client_cert_pkcs11_id))
+      if (!value->GetAsString(&eap_client_cert_pkcs11_id))
         break;
       wifi_network->set_eap_client_cert_pkcs11_id(eap_client_cert_pkcs11_id);
       return true;
     }
     case PROPERTY_INDEX_EAP_CA_CERT_NSS: {
       std::string eap_server_ca_cert_nss_nickname;
-      if (!value.GetAsString(&eap_server_ca_cert_nss_nickname))
+      if (!value->GetAsString(&eap_server_ca_cert_nss_nickname))
         break;
       wifi_network->set_eap_server_ca_cert_nss_nickname(
           eap_server_ca_cert_nss_nickname);
@@ -958,14 +955,14 @@ bool NativeWifiNetworkParser::ParseValue(PropertyIndex index,
     }
     case PROPERTY_INDEX_EAP_USE_SYSTEM_CAS: {
       bool eap_use_system_cas;
-      if (!value.GetAsBoolean(&eap_use_system_cas))
+      if (!value->GetAsBoolean(&eap_use_system_cas))
         break;
       wifi_network->set_eap_use_system_cas(eap_use_system_cas);
       return true;
     }
     case PROPERTY_INDEX_EAP_PASSWORD: {
       std::string eap_passphrase;
-      if (!value.GetAsString(&eap_passphrase))
+      if (!value->GetAsString(&eap_passphrase))
         break;
       wifi_network->set_eap_passphrase(eap_passphrase);
       return true;
@@ -1055,14 +1052,14 @@ bool NativeVirtualNetworkParser::UpdateNetworkFromInfo(
 }
 
 bool NativeVirtualNetworkParser::ParseValue(PropertyIndex index,
-                                            const Value& value,
+                                            Value* value,
                                             Network* network) {
   DCHECK_EQ(TYPE_VPN, network->type());
   VirtualNetwork* virtual_network = static_cast<VirtualNetwork*>(network);
   switch (index) {
     case PROPERTY_INDEX_PROVIDER: {
-      DCHECK_EQ(value.GetType(), Value::TYPE_DICTIONARY);
-      const DictionaryValue& dict = static_cast<const DictionaryValue&>(value);
+      DCHECK_EQ(value->GetType(), Value::TYPE_DICTIONARY);
+      const DictionaryValue& dict = static_cast<const DictionaryValue&>(*value);
       for (DictionaryValue::key_iterator iter = dict.begin_keys();
            iter != dict.end_keys(); ++iter) {
         const std::string& key = *iter;
diff --git a/chrome/browser/chromeos/cros/native_network_parser.h b/chrome/browser/chromeos/cros/native_network_parser.h
index eee1384..29af4fe 100644
--- a/chrome/browser/chromeos/cros/native_network_parser.h
+++ b/chrome/browser/chromeos/cros/native_network_parser.h
@@ -6,8 +6,8 @@
 #define CHROME_BROWSER_CHROMEOS_CROS_NATIVE_NETWORK_PARSER_H_
 #pragma once
 
-#include "chrome/browser/chromeos/cros/network_parser.h"
 #include "base/compiler_specific.h"  // for OVERRIDE
+#include "chrome/browser/chromeos/cros/network_parser.h"
 
 namespace chromeos {
 
@@ -18,9 +18,11 @@ class NativeNetworkDeviceParser : public NetworkDeviceParser {
  public:
   NativeNetworkDeviceParser();
   virtual ~NativeNetworkDeviceParser();
+
   virtual bool ParseValue(PropertyIndex index,
-                          const Value& value,
+                          Value* value,
                           NetworkDevice* device) OVERRIDE;
+
  protected:
   virtual ConnectionType ParseType(const std::string& type) OVERRIDE;
 
@@ -46,11 +48,13 @@ class NativeNetworkParser : public NetworkParser {
  public:
   NativeNetworkParser();
   virtual ~NativeNetworkParser();
+
   static const EnumMapper<PropertyIndex>* property_mapper();
   static const ConnectionType ParseConnectionType(const std::string& type);
+
  protected:
   virtual bool ParseValue(PropertyIndex index,
-                          const Value& value,
+                          Value* value,
                           Network* network) OVERRIDE;
   virtual ConnectionType ParseType(const std::string& type) OVERRIDE;
   virtual ConnectionType ParseTypeFromDictionary(
@@ -58,6 +62,7 @@ class NativeNetworkParser : public NetworkParser {
   virtual ConnectionMode ParseMode(const std::string& mode) OVERRIDE;
   virtual ConnectionState ParseState(const std::string& state) OVERRIDE;
   virtual ConnectionError ParseError(const std::string& error) OVERRIDE;
+
  private:
   DISALLOW_COPY_AND_ASSIGN(NativeNetworkParser);
 };
@@ -67,6 +72,7 @@ class NativeEthernetNetworkParser : public NativeNetworkParser {
  public:
   NativeEthernetNetworkParser();
   virtual ~NativeEthernetNetworkParser();
+
  private:
   // NOTE: Uses base class ParseValue, etc.
 
@@ -79,8 +85,9 @@ class NativeWirelessNetworkParser : public NativeNetworkParser {
   NativeWirelessNetworkParser();
   virtual ~NativeWirelessNetworkParser();
   virtual bool ParseValue(PropertyIndex index,
-                          const Value& value,
+                          Value* value,
                           Network* network) OVERRIDE;
+
  private:
   DISALLOW_COPY_AND_ASSIGN(NativeWirelessNetworkParser);
 };
@@ -90,12 +97,14 @@ class NativeWifiNetworkParser : public NativeWirelessNetworkParser {
   NativeWifiNetworkParser();
   virtual ~NativeWifiNetworkParser();
   virtual bool ParseValue(PropertyIndex index,
-                          const Value& value,
+                          Value* value,
                           Network* network) OVERRIDE;
+
  protected:
   ConnectionSecurity ParseSecurity(const std::string& security);
   EAPMethod ParseEAPMethod(const std::string& method);
   EAPPhase2Auth ParseEAPPhase2Auth(const std::string& auth);
+
  private:
   DISALLOW_COPY_AND_ASSIGN(NativeWifiNetworkParser);
 };
@@ -105,14 +114,14 @@ class NativeCellularNetworkParser : public NativeWirelessNetworkParser {
   NativeCellularNetworkParser();
   virtual ~NativeCellularNetworkParser();
   virtual bool ParseValue(PropertyIndex index,
-                          const Value& value,
+                          Value* value,
                           Network* network) OVERRIDE;
+
  protected:
   ActivationState ParseActivationState(const std::string& state);
-  NetworkTechnology ParseNetworkTechnology(
-      const std::string& technology);
-  NetworkRoamingState ParseRoamingState(
-      const std::string& roaming_state);
+  NetworkTechnology ParseNetworkTechnology(const std::string& technology);
+  NetworkRoamingState ParseRoamingState(const std::string& roaming_state);
+
  private:
   DISALLOW_COPY_AND_ASSIGN(NativeCellularNetworkParser);
 };
@@ -122,20 +131,21 @@ class NativeVirtualNetworkParser : public NativeNetworkParser {
   NativeVirtualNetworkParser();
   virtual ~NativeVirtualNetworkParser();
   virtual bool ParseValue(PropertyIndex index,
-                          const Value& value,
+                          Value* value,
                           Network* network) OVERRIDE;
   virtual bool UpdateNetworkFromInfo(const DictionaryValue& info,
                                      Network* network) OVERRIDE;
+
  protected:
   bool ParseProviderValue(PropertyIndex index,
-                                  const Value& value,
-                                  VirtualNetwork* network);
+                          const Value& value,
+                          VirtualNetwork* network);
   ProviderType ParseProviderType(const std::string& type);
+
  private:
   DISALLOW_COPY_AND_ASSIGN(NativeVirtualNetworkParser);
 };
 
-
 }  // namespace chromeos
 
 #endif  // CHROME_BROWSER_CHROMEOS_CROS_NATIVE_NETWORK_PARSER_H_
diff --git a/chrome/browser/chromeos/cros/network_library.cc b/chrome/browser/chromeos/cros/network_library.cc
index a347ec7..c4f76d1 100644
--- a/chrome/browser/chromeos/cros/network_library.cc
+++ b/chrome/browser/chromeos/cros/network_library.cc
@@ -177,7 +177,7 @@ void NetworkDevice::ParseInfo(const DictionaryValue& info) {
 }
 
 bool NetworkDevice::UpdateStatus(const std::string& key,
-                                 const Value& value,
+                                 Value* value,
                                  PropertyIndex* index) {
   if (device_parser_.get())
     return device_parser_->UpdateStatus(key, value, this, index);
@@ -424,7 +424,7 @@ void Network::InitIPAddress() {
 }
 
 bool Network::UpdateStatus(const std::string& key,
-                           const Value& value,
+                           Value* value,
                            PropertyIndex* index) {
   if (network_parser_.get())
     return network_parser_->UpdateStatus(key, value, this, index);
@@ -2973,13 +2973,14 @@ class NetworkLibraryImplCros : public NetworkLibraryImplBase  {
   // Calbacks.
   static void NetworkStatusChangedHandler(
       void* object, const char* path, const char* key, const Value* value);
-  void UpdateNetworkStatus(
-      const std::string& path, const std::string& key, const Value& value);
+  void UpdateNetworkStatus(const std::string& path,
+                           const std::string& key,
+                           Value* value);
 
   static void NetworkDevicePropertyChangedHandler(
       void* object, const char* path, const char* key, const Value* value);
   void UpdateNetworkDeviceStatus(
-      const std::string& path, const std::string& key, const Value& value);
+      const std::string& path, const std::string& key, Value* value);
 
   static void PinOperationCallback(void* object,
                                    const char* path,
@@ -3166,11 +3167,14 @@ void NetworkLibraryImplCros::NetworkStatusChangedHandler(
   DCHECK(networklib);
   if (key == NULL || value == NULL || path == NULL || object == NULL)
     return;
-  networklib->UpdateNetworkStatus(std::string(path), std::string(key), *value);
+  networklib->UpdateNetworkStatus(std::string(path),
+                                  std::string(key),
+                                  const_cast<Value*>(value));
 }
 
-void NetworkLibraryImplCros::UpdateNetworkStatus(
-    const std::string& path, const std::string& key, const Value& value) {
+void NetworkLibraryImplCros::UpdateNetworkStatus(const std::string& path,
+                                                 const std::string& key,
+                                                 Value* value) {
   CHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
   Network* network = FindNetworkByPath(path);
   if (network) {
@@ -3199,11 +3203,12 @@ void NetworkLibraryImplCros::NetworkDevicePropertyChangedHandler(
     return;
   networklib->UpdateNetworkDeviceStatus(std::string(path),
                                         std::string(key),
-                                        *value);
+                                        const_cast<Value*>(value));
 }
 
-void NetworkLibraryImplCros::UpdateNetworkDeviceStatus(
-    const std::string& path, const std::string& key, const Value& value) {
+void NetworkLibraryImplCros::UpdateNetworkDeviceStatus(const std::string& path,
+                                                       const std::string& key,
+                                                       Value* value) {
   CHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
   NetworkDevice* device = FindNetworkDeviceByPath(path);
   if (device) {
diff --git a/chrome/browser/chromeos/cros/network_library.h b/chrome/browser/chromeos/cros/network_library.h
index 271fe33..d5cd133 100644
--- a/chrome/browser/chromeos/cros/network_library.h
+++ b/chrome/browser/chromeos/cros/network_library.h
@@ -414,7 +414,7 @@ class NetworkDevice {
   // PropertyIndex that was updated in |index|.  |index| may be NULL
   // if not needed.
   bool UpdateStatus(const std::string& key,
-                    const Value& value,
+                    Value* value,
                     PropertyIndex *index);
 
   NativeNetworkDeviceParser* device_parser() { return device_parser_.get(); }
@@ -640,7 +640,7 @@ class Network {
   }
 
   virtual bool UpdateStatus(const std::string& key,
-                            const Value& value,
+                            Value* value,
                             PropertyIndex* index);
 
  protected:
diff --git a/chrome/browser/chromeos/cros/network_parser.cc b/chrome/browser/chromeos/cros/network_parser.cc
index 5d3dfd4..ecdfbdd 100644
--- a/chrome/browser/chromeos/cros/network_parser.cc
+++ b/chrome/browser/chromeos/cros/network_parser.cc
@@ -70,7 +70,7 @@ bool NetworkDeviceParser::UpdateDeviceFromInfo(const DictionaryValue& info,
     bool result = info.GetWithoutPathExpansion(key, &value);
     DCHECK(result);
     if (result)
-      UpdateStatus(key, *value, device, NULL);
+      UpdateStatus(key, value, device, NULL);
   }
   if (VLOG_IS_ON(2)) {
     std::string json;
@@ -82,7 +82,7 @@ bool NetworkDeviceParser::UpdateDeviceFromInfo(const DictionaryValue& info,
 }
 
 bool NetworkDeviceParser::UpdateStatus(const std::string& key,
-                                       const Value& value,
+                                       Value* value,
                                        NetworkDevice* device,
                                        PropertyIndex* index) {
   PropertyIndex found_index = mapper().Get(key);
@@ -94,7 +94,7 @@ bool NetworkDeviceParser::UpdateStatus(const std::string& key,
   }
   if (VLOG_IS_ON(2)) {
     std::string value_json;
-    base::JSONWriter::Write(&value, true, &value_json);
+    base::JSONWriter::Write(value, true, &value_json);
     VLOG(2) << "Updated value on device: "
             << device->device_path() << "[" << key << "] = " << value_json;
   }
@@ -134,7 +134,7 @@ bool NetworkParser::UpdateNetworkFromInfo(const DictionaryValue& info,
     bool res = info.GetWithoutPathExpansion(key, &value);
     DCHECK(res);
     if (res)
-      network->UpdateStatus(key, *value, NULL);
+      network->UpdateStatus(key, value, NULL);
   }
   if (network->unique_id().empty())
     network->CalculateUniqueId();
@@ -145,7 +145,7 @@ bool NetworkParser::UpdateNetworkFromInfo(const DictionaryValue& info,
 }
 
 bool NetworkParser::UpdateStatus(const std::string& key,
-                                 const Value& value,
+                                 Value* value,
                                  Network* network,
                                  PropertyIndex* index) {
   PropertyIndex found_index = mapper().Get(key);
@@ -159,7 +159,7 @@ bool NetworkParser::UpdateStatus(const std::string& key,
   }
   if (VLOG_IS_ON(2)) {
     std::string value_json;
-    base::JSONWriter::Write(&value, true, &value_json);
+    base::JSONWriter::Write(value, true, &value_json);
     VLOG(2) << "Updated value on network: "
             << network->unique_id() << "[" << key << "] = " << value_json;
   }
@@ -167,12 +167,12 @@ bool NetworkParser::UpdateStatus(const std::string& key,
 }
 
 bool NetworkParser::ParseValue(PropertyIndex index,
-                               const Value& value,
+                               Value* value,
                                Network* network) {
   switch (index) {
     case PROPERTY_INDEX_TYPE: {
       std::string type_string;
-      if (value.GetAsString(&type_string)) {
+      if (value->GetAsString(&type_string)) {
         ConnectionType type = ParseType(type_string);
         LOG_IF(ERROR, type != network->type())
             << "Network with mismatched type: " << network->service_path()
@@ -183,14 +183,14 @@ bool NetworkParser::ParseValue(PropertyIndex index,
     }
     case PROPERTY_INDEX_DEVICE: {
       std::string device_path;
-      if (!value.GetAsString(&device_path))
+      if (!value->GetAsString(&device_path))
         break;
       network->set_device_path(device_path);
       return true;
     }
     case PROPERTY_INDEX_NAME: {
       std::string name;
-      if (value.GetAsString(&name)) {
+      if (value->GetAsString(&name)) {
         network->SetName(name);
         return true;
       }
@@ -198,7 +198,7 @@ bool NetworkParser::ParseValue(PropertyIndex index,
     }
     case PROPERTY_INDEX_GUID: {
       std::string unique_id;
-      if (!value.GetAsString(&unique_id))
+      if (!value->GetAsString(&unique_id))
         break;
       network->set_unique_id(unique_id);
       return true;
@@ -206,14 +206,14 @@ bool NetworkParser::ParseValue(PropertyIndex index,
     case PROPERTY_INDEX_PROFILE: {
       // Note: currently this is only provided for non remembered networks.
       std::string profile_path;
-      if (!value.GetAsString(&profile_path))
+      if (!value->GetAsString(&profile_path))
         break;
       network->set_profile_path(profile_path);
       return true;
     }
     case PROPERTY_INDEX_STATE: {
       std::string state_string;
-      if (value.GetAsString(&state_string)) {
+      if (value->GetAsString(&state_string)) {
         network->SetState(ParseState(state_string));
         return true;
       }
@@ -221,7 +221,7 @@ bool NetworkParser::ParseValue(PropertyIndex index,
     }
     case PROPERTY_INDEX_MODE: {
       std::string mode_string;
-      if (value.GetAsString(&mode_string)) {
+      if (value->GetAsString(&mode_string)) {
         network->mode_ = ParseMode(mode_string);
         return true;
       }
@@ -229,7 +229,7 @@ bool NetworkParser::ParseValue(PropertyIndex index,
     }
     case PROPERTY_INDEX_ERROR: {
       std::string error_string;
-      if (value.GetAsString(&error_string)) {
+      if (value->GetAsString(&error_string)) {
         network->error_ = ParseError(error_string);
         return true;
       }
@@ -237,28 +237,28 @@ bool NetworkParser::ParseValue(PropertyIndex index,
     }
     case PROPERTY_INDEX_CONNECTABLE: {
       bool connectable;
-      if (!value.GetAsBoolean(&connectable))
+      if (!value->GetAsBoolean(&connectable))
         break;
       network->set_connectable(connectable);
       return true;
     }
     case PROPERTY_INDEX_IS_ACTIVE: {
       bool is_active;
-      if (!value.GetAsBoolean(&is_active))
+      if (!value->GetAsBoolean(&is_active))
         break;
       network->set_is_active(is_active);
       return true;
     }
     case PROPERTY_INDEX_AUTO_CONNECT: {
       bool auto_connect;
-      if (!value.GetAsBoolean(&auto_connect))
+      if (!value->GetAsBoolean(&auto_connect))
         break;
       network->set_auto_connect(auto_connect);
       return true;
     }
     case PROPERTY_INDEX_SAVE_CREDENTIALS: {
       bool save_credentials;
-      if (!value.GetAsBoolean(&save_credentials))
+      if (!value->GetAsBoolean(&save_credentials))
         break;
       network->set_save_credentials(save_credentials);
       return true;
diff --git a/chrome/browser/chromeos/cros/network_parser.h b/chrome/browser/chromeos/cros/network_parser.h
index 9181551..a06a792 100644
--- a/chrome/browser/chromeos/cros/network_parser.h
+++ b/chrome/browser/chromeos/cros/network_parser.h
@@ -83,16 +83,17 @@ class NetworkDeviceParser {
   virtual bool UpdateDeviceFromInfo(const DictionaryValue& info,
                                     NetworkDevice* device);
   virtual bool UpdateStatus(const std::string& key,
-                            const Value& value,
+                            Value* value,
                             NetworkDevice* device,
                             PropertyIndex* index);
+
  protected:
   // The NetworkDeviceParser does not take ownership of the |mapper|.
   explicit NetworkDeviceParser(const EnumMapper<PropertyIndex>* mapper);
   virtual ~NetworkDeviceParser();
 
   virtual bool ParseValue(PropertyIndex index,
-                          const Value& value,
+                          Value* value,
                           NetworkDevice* device) = 0;
   virtual ConnectionType ParseType(const std::string& type) = 0;
 
@@ -125,7 +126,7 @@ class NetworkParser {
   // property index for the given key.  |index| is filled in even if
   // the update fails.  Returns false upon failure.
   virtual bool UpdateStatus(const std::string& key,
-                            const Value& value,
+                            Value* value,
                             Network* network,
                             PropertyIndex* index);
  protected:
@@ -134,7 +135,7 @@ class NetworkParser {
   virtual ~NetworkParser();
 
   virtual bool ParseValue(PropertyIndex index,
-                          const Value& value,
+                          Value* value,
                           Network* network) = 0;
   virtual ConnectionType ParseType(const std::string& type) = 0;
   virtual ConnectionType ParseTypeFromDictionary(
diff --git a/chrome/browser/extensions/extension_bookmarks_module.cc b/chrome/browser/extensions/extension_bookmarks_module.cc
index dce4b6f..f8b2c78 100644
--- a/chrome/browser/extensions/extension_bookmarks_module.cc
+++ b/chrome/browser/extensions/extension_bookmarks_module.cc
@@ -285,8 +285,7 @@ bool GetBookmarksFunction::RunImpl() {
   scoped_ptr<ListValue> json(new ListValue());
   Value* arg0;
   EXTENSION_FUNCTION_VALIDATE(args_->Get(0, &arg0));
-  if (arg0->IsType(Value::TYPE_LIST)) {
-    const ListValue* ids = static_cast<const ListValue*>(arg0);
+  if (const ListValue* ids = arg0->AsList()) {
     size_t count = ids->GetSize();
     EXTENSION_FUNCTION_VALIDATE(count > 0);
     for (size_t i = 0; i < count; ++i) {
diff --git a/chrome/browser/extensions/extension_tabs_module.cc b/chrome/browser/extensions/extension_tabs_module.cc
index a949b4d..9a6ded9 100644
--- a/chrome/browser/extensions/extension_tabs_module.cc
+++ b/chrome/browser/extensions/extension_tabs_module.cc
@@ -417,8 +417,7 @@ bool CreateWindowFunction::RunImpl() {
         std::string url_string;
         url_value->GetAsString(&url_string);
         url_strings.push_back(url_string);
-      } else if (url_value->IsType(Value::TYPE_LIST)) {
-        const ListValue* url_list = static_cast<const ListValue*>(url_value);
+      } else if (const ListValue* url_list = url_value->AsList()) {
         for (size_t i = 0; i < url_list->GetSize(); ++i) {
           std::string url_string;
           EXTENSION_FUNCTION_VALIDATE(url_list->GetString(i, &url_string));
diff --git a/chrome/browser/extensions/extension_webrequest_api_unittest.cc b/chrome/browser/extensions/extension_webrequest_api_unittest.cc
index 8398433..0791a71 100644
--- a/chrome/browser/extensions/extension_webrequest_api_unittest.cc
+++ b/chrome/browser/extensions/extension_webrequest_api_unittest.cc
@@ -477,13 +477,12 @@ TEST_P(ExtensionWebRequestHeaderModificationTest, TestModifications) {
 
     scoped_ptr<Value> event_arg_value(
         JSONStringValueSerializer(event_arg_string).Deserialize(NULL, NULL));
-    ASSERT_TRUE(event_arg_value.get() &&
-                event_arg_value->IsType(Value::TYPE_LIST));
+    ASSERT_TRUE(event_arg_value.get());
+    ListValue* list = event_arg_value->AsList();
+    ASSERT_TRUE(list);
 
     DictionaryValue* event_arg_dict = NULL;
-    ASSERT_TRUE(
-        static_cast<ListValue*>(event_arg_value.get())->GetDictionary(
-            0, &event_arg_dict));
+    ASSERT_TRUE(list->GetDictionary(0, &event_arg_dict));
 
     ListValue* request_headers = NULL;
     ASSERT_TRUE(event_arg_dict->GetList(keys::kRequestHeadersKey,
diff --git a/chrome/common/json_value_serializer_unittest.cc b/chrome/common/json_value_serializer_unittest.cc
index 541ac8c..abb3684 100644
--- a/chrome/common/json_value_serializer_unittest.cc
+++ b/chrome/common/json_value_serializer_unittest.cc
@@ -195,8 +195,9 @@ namespace {
 
 void ValidateJsonList(const std::string& json) {
   scoped_ptr<Value> root(base::JSONReader::Read(json, false));
-  ASSERT_TRUE(root.get() && root->IsType(Value::TYPE_LIST));
-  ListValue* list = static_cast<ListValue*>(root.get());
+  ASSERT_TRUE(root.get());
+  ListValue* list = root->AsList();
+  ASSERT_TRUE(list);
   ASSERT_EQ(1U, list->GetSize());
   Value* elt = NULL;
   ASSERT_TRUE(list->Get(0, &elt));
@@ -219,8 +220,9 @@ TEST(JSONValueSerializerTest, JSONReaderComments) {
 
   // It's ok to have a comment in a string.
   root.reset(base::JSONReader::Read("[\"// ok\\n /* foo */ \"]", false));
-  ASSERT_TRUE(root.get() && root->IsType(Value::TYPE_LIST));
-  ListValue* list = static_cast<ListValue*>(root.get());
+  ASSERT_TRUE(root.get());
+  ListValue* list = root->AsList();
+  ASSERT_TRUE(list);
   ASSERT_EQ(1U, list->GetSize());
   Value* elt = NULL;
   ASSERT_TRUE(list->Get(0, &elt));
diff --git a/chrome/renderer/extensions/extension_process_bindings.cc b/chrome/renderer/extensions/extension_process_bindings.cc
index d96743c..077c524 100644
--- a/chrome/renderer/extensions/extension_process_bindings.cc
+++ b/chrome/renderer/extensions/extension_process_bindings.cc
@@ -467,12 +467,12 @@ class ExtensionImpl : public ExtensionBase {
 
     // Since we do the serialization in the v8 extension, we should always get
     // valid JSON.
-    if (!value_args.get() || !value_args->IsType(Value::TYPE_LIST)) {
+    if (!value_args.get() || !value_args->AsList()) {
       NOTREACHED() << "Invalid JSON passed to StartRequest.";
       return v8::Undefined();
     }
 
-    return StartRequestCommon(args, static_cast<ListValue*>(value_args.get()));
+    return StartRequestCommon(args, value_args->AsList());
   }
 
   static bool ConvertImageDataToBitmapValue(
diff --git a/chrome/test/automation/automation_json_requests.cc b/chrome/test/automation/automation_json_requests.cc
index ab0de31..ecd932e 100644
--- a/chrome/test/automation/automation_json_requests.cc
+++ b/chrome/test/automation/automation_json_requests.cc
@@ -187,11 +187,11 @@ bool SendExecuteJavascriptJSONRequest(
 
   JSONStringValueSerializer deserializer(json);
   Value* value = deserializer.Deserialize(NULL, NULL);
-  if (!value || !value->IsType(Value::TYPE_LIST)) {
+  if (!value || !value->AsList()) {
     LOG(ERROR) << "Unable to deserialize returned JSON";
     return false;
   }
-  scoped_ptr<ListValue> list(static_cast<ListValue*>(value));
+  scoped_ptr<ListValue> list(value->AsList());
   return list->Remove(0, result);
 }
 
@@ -297,9 +297,9 @@ bool SendGetCookiesJSONRequest(
   if (!reply_dict.Remove("cookies", &cookies_unscoped_value))
     return false;
   scoped_ptr<Value> cookies_value(cookies_unscoped_value);
-  if (!cookies_value->IsType(Value::TYPE_LIST))
+  if (!cookies_value->AsList())
     return false;
-  *cookies = static_cast<ListValue*>(cookies_value.release());
+  *cookies = cookies_value->AsList();
   return true;
 }
 
diff --git a/chrome/test/automation/javascript_execution_controller.cc b/chrome/test/automation/javascript_execution_controller.cc
index 5be6b98..e4702c5 100644
--- a/chrome/test/automation/javascript_execution_controller.cc
+++ b/chrome/test/automation/javascript_execution_controller.cc
@@ -1,4 +1,4 @@
-// Copyright (c) 2010 The Chromium Authors. All rights reserved.
+// Copyright (c) 2011 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.
 
@@ -89,11 +89,11 @@ bool JavaScriptExecutionController::ExecuteAndParseHelper(
   bool success;
   std::string evaluation_error;
   Value* evaluation_result_value;
-  if (!root_value->IsType(Value::TYPE_LIST)) {
+  ListValue* list = root_value->AsList();
+  if (!list) {
     LOG(ERROR) << "JSON response was not in correct format";
     return false;
   }
-  ListValue* list = static_cast<ListValue*>(root_value.get());
   if (!list->GetBoolean(0, &success) ||
       !list->GetString(1, &evaluation_error) ||
       !list->Remove(2, &evaluation_result_value)) {
diff --git a/chrome/test/automation/javascript_message_utils.h b/chrome/test/automation/javascript_message_utils.h
index e4b61f4..1ccdc17 100644
--- a/chrome/test/automation/javascript_message_utils.h
+++ b/chrome/test/automation/javascript_message_utils.h
@@ -51,11 +51,11 @@ struct ValueConversionTraits<std::vector<T> > {
     }
     return value;
   }
-  static bool SetFromValue(const Value* value, std::vector<T>* t) {
-    if (!value->IsType(Value::TYPE_LIST))
+  static bool SetFromValue(Value* value, std::vector<T>* t) {
+    ListValue* list_value = value->AsList();
+    if (!list_value)
       return false;
 
-    const ListValue* list_value = static_cast<const ListValue*>(value);
     ListValue::const_iterator iter;
     for (iter = list_value->begin(); iter != list_value->end(); ++iter) {
       if (!ValueConversionTraits<T>::CanConvert(*iter))
diff --git a/chrome/test/automation/tab_proxy.cc b/chrome/test/automation/tab_proxy.cc
index 49cd00c..d30fd7d 100644
--- a/chrome/test/automation/tab_proxy.cc
+++ b/chrome/test/automation/tab_proxy.cc
@@ -266,9 +266,9 @@ bool TabProxy::ExecuteAndExtractString(const std::wstring& frame_xpath,
   if (!succeeded)
     return false;
 
-  DCHECK(root->IsType(Value::TYPE_LIST));
+  DCHECK(root->AsList());
   Value* value = NULL;
-  succeeded = static_cast<ListValue*>(root)->Get(0, &value);
+  succeeded = root->AsList()->Get(0, &value);
   if (succeeded) {
     string16 read_value;
     succeeded = value->GetAsString(&read_value);
@@ -291,9 +291,9 @@ bool TabProxy::ExecuteAndExtractBool(const std::wstring& frame_xpath,
     return false;
 
   bool read_value = false;
-  DCHECK(root->IsType(Value::TYPE_LIST));
+  DCHECK(root->AsList());
   Value* value = NULL;
-  succeeded = static_cast<ListValue*>(root)->Get(0, &value);
+  succeeded = root->AsList()->Get(0, &value);
   if (succeeded) {
     succeeded = value->GetAsBoolean(&read_value);
     if (succeeded) {
@@ -314,9 +314,9 @@ bool TabProxy::ExecuteAndExtractInt(const std::wstring& frame_xpath,
     return false;
 
   int read_value = 0;
-  DCHECK(root->IsType(Value::TYPE_LIST));
+  DCHECK(root->AsList());
   Value* value = NULL;
-  succeeded = static_cast<ListValue*>(root)->Get(0, &value);
+  succeeded = root->AsList()->Get(0, &value);
   if (succeeded) {
     succeeded = value->GetAsInteger(&read_value);
     if (succeeded) {
diff --git a/chrome/test/automation/value_conversion_traits.cc b/chrome/test/automation/value_conversion_traits.cc
index f5c1f2c..16d6510 100644
--- a/chrome/test/automation/value_conversion_traits.cc
+++ b/chrome/test/automation/value_conversion_traits.cc
@@ -71,14 +71,15 @@ Value* ValueConversionTraits<ListValue*>::CreateValueFrom(const ListValue* t) {
 
 bool ValueConversionTraits<ListValue*>::SetFromValue(const Value* value,
                                                      ListValue** t) {
-  if (!value->IsType(Value::TYPE_LIST))
+  ListValue* list = const_cast<Value*>(value)->AsList();
+  if (!list)
     return false;
-  *t = static_cast<const ListValue*>(value)->DeepCopy();
+  *t = list->DeepCopy();
   return true;
 }
 
 bool ValueConversionTraits<ListValue*>::CanConvert(const Value* value) {
-  return value->IsType(Value::TYPE_LIST);
+  return const_cast<Value*>(value)->AsList();
 }
 
 Value* ValueConversionTraits<DictionaryValue*>::CreateValueFrom(
diff --git a/chrome/test/base/ui_test_utils.cc b/chrome/test/base/ui_test_utils.cc
index d087e68..2234ba2 100644
--- a/chrome/test/base/ui_test_utils.cc
+++ b/chrome/test/base/ui_test_utils.cc
@@ -206,10 +206,10 @@ bool ExecuteJavaScriptHelper(RenderViewHost* render_view_host,
   json.append("]");
 
   scoped_ptr<Value> root_val(base::JSONReader::Read(json, true));
-  if (!root_val->IsType(Value::TYPE_LIST))
+  ListValue* list = root_val->AsList();
+  if (!list)
     return false;
 
-  ListValue* list = static_cast<ListValue*>(root_val.get());
   Value* result_val;
   if (!list || !list->GetSize() ||
       !list->Remove(0, &result_val))  // Remove gives us ownership of the value.
@@ -925,9 +925,9 @@ class SnapshotTaker {
     // Parse the JSON.
     std::vector<int> dimensions;
     scoped_ptr<Value> value(base::JSONReader::Read(json, true));
-    if (!value->IsType(Value::TYPE_LIST))
+    ListValue* list = value->AsList();
+    if (!list)
       return false;
-    ListValue* list = static_cast<ListValue*>(value.get());
     int width, height;
     if (!list->GetInteger(0, &width) || !list->GetInteger(1, &height))
       return false;
diff --git a/chrome/test/perf/dom_checker_uitest.cc b/chrome/test/perf/dom_checker_uitest.cc
index 6ca9c1a..4196666 100644
--- a/chrome/test/perf/dom_checker_uitest.cc
+++ b/chrome/test/perf/dom_checker_uitest.cc
@@ -175,12 +175,11 @@ class DomCheckerTest : public UITest {
     if (!value.get())
       return false;
 
-    EXPECT_TRUE(value->IsType(Value::TYPE_LIST));
-    if (!value->IsType(Value::TYPE_LIST))
+    EXPECT_TRUE(value->AsList());
+    ListValue* list_value = value->AsList();
+    if (!list_value)
       return false;
 
-    ListValue* list_value = static_cast<ListValue*>(value.get());
-
     // The parsed JSON object will be an array of strings, each of which is a
     // test failure. Add those strings to the results set.
     ListValue::const_iterator it = list_value->begin();
diff --git a/chrome/test/webdriver/commands/response.cc b/chrome/test/webdriver/commands/response.cc
index 1c09d39..882dbeb 100644
--- a/chrome/test/webdriver/commands/response.cc
+++ b/chrome/test/webdriver/commands/response.cc
@@ -46,7 +46,7 @@ void Response::SetStatus(ErrorCode status) {
   data_.SetInteger(kStatusKey, status);
 }
 
-const Value* Response::GetValue() const {
+Value* Response::GetValue() const {
   Value* out = NULL;
   LOG_IF(WARNING, !data_.Get(kValueKey, &out))
       << "Accessing unset response value.";  // Should never happen.
diff --git a/chrome/test/webdriver/commands/response.h b/chrome/test/webdriver/commands/response.h
index 9c44e60..0d25c48 100644
--- a/chrome/test/webdriver/commands/response.h
+++ b/chrome/test/webdriver/commands/response.h
@@ -28,7 +28,7 @@ class Response {
   void SetStatus(ErrorCode status);
 
   // Ownership of the returned pointer is kept by this object.
-  const Value* GetValue() const;
+  Value* GetValue() const;
 
   // Sets the |value| of this response, assuming ownership of the object in the
   // process.
diff --git a/chrome/test/webdriver/webdriver_dispatch.cc b/chrome/test/webdriver/webdriver_dispatch.cc
index a9dcd4a..e079f12 100644
--- a/chrome/test/webdriver/webdriver_dispatch.cc
+++ b/chrome/test/webdriver/webdriver_dispatch.cc
@@ -152,7 +152,7 @@ void PrepareHttpResponse(const Response& command_response,
     // and kMethodNotAllowed should be detected before creating
     // a command_response, and should thus not need conversion.
     case kSeeOther: {
-      const Value* const value = command_response.GetValue();
+      Value* value = command_response.GetValue();
       std::string location;
       if (!value->GetAsString(&location)) {
         // This should never happen.
@@ -173,8 +173,9 @@ void PrepareHttpResponse(const Response& command_response,
       break;
 
     case kMethodNotAllowed: {
-      const Value* const value = command_response.GetValue();
-      if (!value->IsType(Value::TYPE_LIST)) {
+      Value* value = command_response.GetValue();
+      ListValue* list_value = value->AsList();
+      if (!list_value) {
         // This should never happen.
         http_response->set_status(HttpResponse::kInternalServerError);
         http_response->SetBody(
@@ -183,8 +184,6 @@ void PrepareHttpResponse(const Response& command_response,
         return;
       }
 
-      const ListValue* const list_value =
-          static_cast<const ListValue* const>(value);
       std::vector<std::string> allowed_methods;
       for (size_t i = 0; i < list_value->GetSize(); ++i) {
         std::string method;
diff --git a/chrome/test/webdriver/webdriver_session.cc b/chrome/test/webdriver/webdriver_session.cc
index 1a764a8..c3a7c11 100644
--- a/chrome/test/webdriver/webdriver_session.cc
+++ b/chrome/test/webdriver/webdriver_session.cc
@@ -1240,9 +1240,9 @@ Error* Session::ExecuteFindElementScriptAndParse(
     virtual ~FindElementsParser() { }
 
     virtual bool Parse(base::Value* value) const OVERRIDE {
-      if (!value->IsType(Value::TYPE_LIST))
+      ListValue* list = value->AsList();
+      if (!list)
         return false;
-      ListValue* list = static_cast<ListValue*>(value);
       for (size_t i = 0; i < list->GetSize(); ++i) {
         ElementId element;
         Value* element_value = NULL;
diff --git a/content/browser/speech/speech_recognition_request.cc b/content/browser/speech/speech_recognition_request.cc
index 645e75d..4cc8e19 100644
--- a/content/browser/speech/speech_recognition_request.cc
+++ b/content/browser/speech/speech_recognition_request.cc
@@ -60,12 +60,12 @@ bool ParseServerResponse(const std::string& response_body,
     return false;
   }
   DCHECK(hypotheses_value);
-  if (!hypotheses_value->IsType(Value::TYPE_LIST)) {
+  const ListValue* hypotheses_list = hypotheses_value->AsList();
+  if (!hypotheses_list) {
     VLOG(1) << "ParseServerResponse: Unexpected hypotheses type "
             << hypotheses_value->GetType();
     return false;
   }
-  const ListValue* hypotheses_list = static_cast<ListValue*>(hypotheses_value);
 
   size_t index = 0;
   for (; index < hypotheses_list->GetSize(); ++index) {
diff --git a/content/renderer/web_ui_bindings.cc b/content/renderer/web_ui_bindings.cc
index 97037a4..98a83c5 100644
--- a/content/renderer/web_ui_bindings.cc
+++ b/content/renderer/web_ui_bindings.cc
@@ -77,7 +77,7 @@ void WebUIBindings::send(const CppArgumentList& args, CppVariant* result) {
       return;
 
     content.reset(CreateValueFromCppVariant(args[1]));
-    CHECK(content->IsType(Value::TYPE_LIST));
+    CHECK(content->AsList());
   } else {
     content.reset(new ListValue());
   }