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

base/metrics/statistics_recorder.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 "base/metrics/statistics_recorder.h"
 
 #include "base/debug/leak_annotations.h"
 #include "base/logging.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/metrics/histogram.h"
@@ skipping 290 matching lines @@
   }
   base::AutoLock auto_lock(*lock_);
   histograms_ = new HistogramMap;
   ranges_ = new RangesMap;
 }
 
 StatisticsRecorder::~StatisticsRecorder() {
   DCHECK(histograms_ && ranges_ && lock_);
   if (dump_on_exit_) {
     string output;
-    WriteGraph("", &output);
+    WriteGraph(std::string(), &output);
     DLOG(INFO) << output;
   }
 
   // Clean up.
   scoped_ptr<HistogramMap> histograms_deleter;
   scoped_ptr<RangesMap> ranges_deleter;
   // We don't delete lock_ on purpose to avoid having to properly protect
   // against it going away after we checked for NULL in the static methods.
   {
     base::AutoLock auto_lock(*lock_);
     histograms_deleter.reset(histograms_);
     ranges_deleter.reset(ranges_);
     histograms_ = NULL;
     ranges_ = NULL;
   }
   // We are going to leak the histograms and the ranges.
 }
 
 
 // static
 StatisticsRecorder::HistogramMap* StatisticsRecorder::histograms_ = NULL;
 // static
 StatisticsRecorder::RangesMap* StatisticsRecorder::ranges_ = NULL;
 // static
 base::Lock* StatisticsRecorder::lock_ = NULL;
 // static
 bool StatisticsRecorder::dump_on_exit_ = false;
 
 }  // namespace base