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

base/test/trace_event_analyzer.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/test/trace_event_analyzer.h"
 
 #include <algorithm>
 #include <math.h>
 #include <set>
 
@@ skipping 122 matching lines @@
 
 bool TraceEvent::HasNumberArg(const std::string& name) const {
   return (arg_numbers.find(name) != arg_numbers.end());
 }
 
 std::string TraceEvent::GetKnownArgAsString(const std::string& name) const {
   std::string arg_string;
   if (GetArgAsString(name, &arg_string))
     return arg_string;
   NOTREACHED();
-  return "";
+  return std::string();
 }
 
 double TraceEvent::GetKnownArgAsDouble(const std::string& name) const {
   double arg_double;
   if (GetArgAsNumber(name, &arg_double))
     return arg_double;
   NOTREACHED();
   return 0;
 }
 
@@ skipping 800 matching lines @@
   end_position = (end_position < events.size()) ? end_position : events.size();
   size_t count = 0u;
   for (size_t i = begin_position; i < end_position; ++i) {
     if (query.Evaluate(*events.at(i)))
       ++count;
   }
   return count;
 }
 
 }  // namespace trace_analyzer