Reland of ExtensionFunction: don't pass ownership of base::Value by raw pointer.

chrome/browser/extensions/api/language_settings_private/language_settings_private_api.cc

Index: chrome/browser/extensions/api/language_settings_private/language_settings_private_api.cc
diff --git a/chrome/browser/extensions/api/language_settings_private/language_settings_private_api.cc b/chrome/browser/extensions/api/language_settings_private/language_settings_private_api.cc
index b7fefdcca05fa1b434cb40733603af5488858fc1..167a6aee70bb46e815c83eca06d816c807aef3a3 100644
--- a/chrome/browser/extensions/api/language_settings_private/language_settings_private_api.cc
+++ b/chrome/browser/extensions/api/language_settings_private/language_settings_private_api.cc
@@ -14,6 +14,7 @@
 
 #include "base/i18n/rtl.h"
 #include "base/memory/linked_ptr.h"
+#include "base/memory/ptr_util.h"
 #include "base/strings/string16.h"
 #include "base/strings/string_split.h"
 #include "base/strings/string_util.h"
@@ -241,7 +242,7 @@
 
     language_list->Append(language.ToValue());
   }
-  return RespondNow(OneArgument(language_list.release()));
+  return RespondNow(OneArgument(std::move(language_list)));
 }
 
 LanguageSettingsPrivateSetLanguageListFunction::
@@ -302,7 +303,7 @@
   SpellcheckCustomDictionary* dictionary = service->GetCustomDictionary();
 
   if (dictionary->IsLoaded())
-    return RespondNow(OneArgument(GetSpellcheckWords().release()));
+    return RespondNow(OneArgument(GetSpellcheckWords()));
 
   dictionary->AddObserver(this);
   AddRef();  // Balanced in OnCustomDictionaryLoaded().
@@ -314,7 +315,7 @@
   SpellcheckService* service =
       SpellcheckServiceFactory::GetForContext(browser_context());
   service->GetCustomDictionary()->RemoveObserver(this);
-  Respond(OneArgument(GetSpellcheckWords().release()));
+  Respond(OneArgument(GetSpellcheckWords()));
   Release();
 }
 
@@ -359,7 +360,8 @@
       SpellcheckServiceFactory::GetForContext(browser_context());
   bool success = service->GetCustomDictionary()->AddWord(params->word);
 
-  return RespondNow(OneArgument(new base::FundamentalValue(success)));
+  return RespondNow(
+      OneArgument(base::MakeUnique<base::FundamentalValue>(success)));
 }
 
 LanguageSettingsPrivateRemoveSpellcheckWordFunction::
@@ -381,7 +383,8 @@
       SpellcheckServiceFactory::GetForContext(browser_context());
   bool success = service->GetCustomDictionary()->RemoveWord(params->word);
 
-  return RespondNow(OneArgument(new base::FundamentalValue(success)));
+  return RespondNow(
+      OneArgument(base::MakeUnique<base::FundamentalValue>(success)));
 }
 
 LanguageSettingsPrivateGetTranslateTargetLanguageFunction::
@@ -395,8 +398,8 @@
 
 ExtensionFunction::ResponseAction
 LanguageSettingsPrivateGetTranslateTargetLanguageFunction::Run() {
-  return RespondNow(OneArgument(new base::StringValue(
-      TranslateService::GetTargetLanguage(
+  return RespondNow(OneArgument(
+      base::MakeUnique<base::StringValue>(TranslateService::GetTargetLanguage(
           chrome_details_.GetProfile()->GetPrefs()))));
 }