Rewrite std::string("") to std::string(), Linux edition.

chrome/common/extensions/features/complex_feature.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/common/extensions/features/complex_feature.h"
 
 #include "chrome/common/extensions/features/simple_feature.h"
 
 namespace extensions {
 
@@ skipping 58 matching lines @@
 
 bool ComplexFeature::IsInternal() const {
   NOTREACHED();
   return false;
 }
 
 std::string ComplexFeature::GetAvailabilityMessage(AvailabilityResult result,
                                                    Manifest::Type type,
                                                    const GURL& url) const {
   if (result == IS_AVAILABLE)
-    return "";
+    return std::string();
 
   // TODO(justinlin): Form some kind of combined availabilities/messages from
   // SimpleFeatures.
   return features_[0]->GetAvailabilityMessage(result, type, url);
 }
 
 }  // namespace extensions