Rewrite scoped_ptr<T>(NULL) to use the default ctor in chrome/.

chrome/browser/extensions/api/declarative/declarative_rule.h

 // Copyright (c) 2013 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.
 //
 // DeclarativeRule<>, DeclarativeConditionSet<>, and DeclarativeActionSet<>
 // templates usable with multiple different declarativeFoo systems.  These are
 // templated on the Condition and Action types that define the behavior of a
 // particular declarative event.
 
 #ifndef CHROME_BROWSER_EXTENSIONS_API_DECLARATIVE_DECLARATIVE_RULE_H__
@@ skipping 281 matching lines @@
     const AnyVector& conditions,
     std::string* error) {
   Conditions result;
 
   for (AnyVector::const_iterator i = conditions.begin();
        i != conditions.end(); ++i) {
     CHECK(i->get());
     scoped_ptr<ConditionT> condition =
         ConditionT::Create(url_matcher_condition_factory, **i, error);
     if (!error->empty())
-      return scoped_ptr<DeclarativeConditionSet>(NULL);
+      return scoped_ptr<DeclarativeConditionSet>();
     result.push_back(make_linked_ptr(condition.release()));
   }
 
   URLMatcherIdToCondition match_id_to_condition;
   std::vector<const ConditionT*> conditions_without_urls;
   URLMatcherConditionSet::Vector condition_sets;
 
   for (typename Conditions::const_iterator i = result.begin();
        i != result.end(); ++i) {
     condition_sets.clear();
@@ skipping 39 matching lines @@
   *error = "";
   *bad_message = false;
   Actions result;
 
   for (AnyVector::const_iterator i = actions.begin();
        i != actions.end(); ++i) {
     CHECK(i->get());
     scoped_refptr<const ActionT> action =
         ActionT::Create(**i, error, bad_message);
     if (!error->empty() || *bad_message)
-      return scoped_ptr<DeclarativeActionSet>(NULL);
+      return scoped_ptr<DeclarativeActionSet>();
     result.push_back(action);
   }
 
   return scoped_ptr<DeclarativeActionSet>(new DeclarativeActionSet(result));
 }
 
 template<typename ActionT>
 void DeclarativeActionSet<ActionT>::Apply(
     const std::string& extension_id,
     const base::Time& extension_install_time,
@@ skipping 102 matching lines @@
 }
 
 template<typename ConditionT, typename ActionT>
 int DeclarativeRule<ConditionT, ActionT>::GetMinimumPriority() const {
   return actions_->GetMinimumPriority();
 }
 
 }  // namespace extensions
 
 #endif  // CHROME_BROWSER_EXTENSIONS_API_DECLARATIVE_DECLARATIVE_RULE_H__