Change PrefStore::ReadResult to a boolean.

chrome/browser/prefs/pref_service.cc

 // Copyright (c) 2012 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/prefs/pref_service.h"
 
 #include <algorithm>
 
 #include "base/bind.h"
 #include "base/command_line.h"
@@ skipping 713 matching lines @@
 
   const Preference* pref = FindPreference(path);
   if (!pref) {
     NOTREACHED() << "Trying to get an unregistered pref: " << path;
     return NULL;
   }
 
   // Look for an existing preference in the user store. If it doesn't
   // exist, return NULL.
   base::Value* value = NULL;
-  if (user_pref_store_->GetMutableValue(path, &value) != PrefStore::READ_OK)
+  if (!user_pref_store_->GetMutableValue(path, &value))
     return NULL;
 
   if (!value->IsType(pref->GetType())) {
     NOTREACHED() << "Pref value type doesn't match registered type.";
     return NULL;
   }
 
   return value;
 }
 
 const base::Value* PrefService::GetDefaultPrefValue(const char* path) const {
   DCHECK(CalledOnValidThread());
   // Lookup the preference in the default store.
   const base::Value* value = NULL;
-  if (default_store_->GetValue(path, &value) != PrefStore::READ_OK) {
+  if (!default_store_->GetValue(path, &value)) {
     NOTREACHED() << "Default value missing for pref: " << path;
     return NULL;
   }
   return value;
 }
 
 const ListValue* PrefService::GetList(const char* path) const {
   DCHECK(CalledOnValidThread());
 
   const Preference* pref = FindPreference(path);
@@ skipping 165 matching lines @@
     return NULL;
   }
   if (pref->GetType() != type) {
     NOTREACHED() << "Wrong type for GetMutableValue: " << path;
     return NULL;
   }
 
   // Look for an existing preference in the user store. If it doesn't
   // exist or isn't the correct type, create a new user preference.
   Value* value = NULL;
-  if (user_pref_store_->GetMutableValue(path, &value) != PrefStore::READ_OK ||
+  if (!user_pref_store_->GetMutableValue(path, &value) ||
       !value->IsType(type)) {
     if (type == Value::TYPE_DICTIONARY) {
       value = new DictionaryValue;
     } else if (type == Value::TYPE_LIST) {
       value = new ListValue;
     } else {
       NOTREACHED();
     }
     user_pref_store_->SetValueSilently(path, value);
   }
@@ skipping 113 matching lines @@
   return pref_value_store()->PrefValueFromDefaultStore(name_.c_str());
 }
 
 bool PrefService::Preference::IsUserModifiable() const {
   return pref_value_store()->PrefValueUserModifiable(name_.c_str());
 }
 
 bool PrefService::Preference::IsExtensionModifiable() const {
   return pref_value_store()->PrefValueExtensionModifiable(name_.c_str());
 }