Change PrefStore::ReadResult to a boolean.

chrome/service/service_process_prefs.cc

 // 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.
 
 #include "chrome/service/service_process_prefs.h"
 
 #include "base/values.h"
 
 ServiceProcessPrefs::ServiceProcessPrefs(
     const FilePath& pref_filename,
     base::MessageLoopProxy* file_message_loop_proxy)
     : prefs_(new JsonPrefStore(pref_filename, file_message_loop_proxy)) {
 }
 
 ServiceProcessPrefs::~ServiceProcessPrefs() {}
 
 void ServiceProcessPrefs::ReadPrefs() {
   prefs_->ReadPrefs();
 }
 
 void ServiceProcessPrefs::WritePrefs() {
   prefs_->CommitPendingWrite();
 }
 
 std::string ServiceProcessPrefs::GetString(
     const std::string& key,
     const std::string& default_value) const {
   const Value* value;
   std::string result;
-  if (prefs_->GetValue(key, &value) != PersistentPrefStore::READ_OK ||
-      !value->GetAsString(&result)) {
+  if (!prefs_->GetValue(key, &value) || !value->GetAsString(&result))
     return default_value;
-  }
+
   return result;
 }
 
 void ServiceProcessPrefs::SetString(const std::string& key,
                                     const std::string& value) {
   prefs_->SetValue(key, Value::CreateStringValue(value));
 }
 
 bool ServiceProcessPrefs::GetBoolean(const std::string& key,
                                      bool default_value) const {
   const Value* value;
   bool result = false;
-  if (prefs_->GetValue(key, &value) != PersistentPrefStore::READ_OK ||
-      !value->GetAsBoolean(&result)) {
+  if (!prefs_->GetValue(key, &value) || !value->GetAsBoolean(&result))
     return default_value;
-  }
+
   return result;
 }
 
 void ServiceProcessPrefs::SetBoolean(const std::string& key, bool value) {
   prefs_->SetValue(key, Value::CreateBooleanValue(value));
 }
 
 int ServiceProcessPrefs::GetInt(const std::string& key,
                                 int default_value) const {
   const Value* value;
   int result = default_value;
-  if (prefs_->GetValue(key, &value) != PersistentPrefStore::READ_OK ||
-      !value->GetAsInteger(&result)) {
+  if (!prefs_->GetValue(key, &value) || !value->GetAsInteger(&result))
     return default_value;
-  }
+
   return result;
 }
 
 void ServiceProcessPrefs::SetInt(const std::string& key, int value) {
   prefs_->SetValue(key, Value::CreateIntegerValue(value));
 }
 
 const DictionaryValue* ServiceProcessPrefs::GetDictionary(
     const std::string& key) const {
   const Value* value;
-  if (prefs_->GetValue(key, &value) != PersistentPrefStore::READ_OK ||
+  if (!prefs_->GetValue(key, &value) ||
       !value->IsType(Value::TYPE_DICTIONARY)) {
     return NULL;
   }
 
   return static_cast<const DictionaryValue*>(value);
 }
 
 const base::ListValue* ServiceProcessPrefs::GetList(
     const std::string& key) const {
   const Value* value;
-  if (prefs_->GetValue(key, &value) != PersistentPrefStore::READ_OK ||
-    !value->IsType(Value::TYPE_LIST)) {
-      return NULL;
-  }
+  if (!prefs_->GetValue(key, &value) || !value->IsType(Value::TYPE_LIST))
+    return NULL;
 
   return static_cast<const ListValue*>(value);
 }
 
 void ServiceProcessPrefs::SetValue(const std::string& key, base::Value* value) {
   prefs_->SetValue(key, value);
 }
 
 void ServiceProcessPrefs::RemovePref(const std::string& key) {
   prefs_->RemoveValue(key);
 }