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

chrome/test/perf/tab_switching_test.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/command_line.h"
 #include "base/environment.h"
 #include "base/file_util.h"
 #include "base/files/file_path.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/path_service.h"
@@ skipping 51 matching lines @@
     UITest::SetUp();
   }
 
   static const int kNumCycles = 5;
 
   void PrintTimings(const char* label, TimeDelta timings[kNumCycles],
     bool important) {
       std::string times;
       for (int i = 0; i < kNumCycles; ++i)
         base::StringAppendF(&times, "%.2f,", timings[i].InMillisecondsF());
-      perf_test::PrintResultList("times", "", label, times, "ms", important);
+      perf_test::PrintResultList(
+          "times", std::string(), label, times, "ms", important);
   }
 
   void RunTabSwitchingUITest(const char* label, bool important) {
     // Shut down from window UITest sets up automatically.
     UITest::TearDown();
 
     TimeDelta timings[kNumCycles];
     for (int i = 0; i < kNumCycles; ++i) {
       // Prepare for this test run.
       SetUp();
@@ skipping 110 matching lines @@
   RunTabSwitchingUITest("t", true);
 }
 
 // Started failing with a webkit roll in r49936. See http://crbug.com/46751
 TEST_F(TabSwitchingUITest, DISABLED_TabSwitchRef) {
   UseReferenceBuild();
   RunTabSwitchingUITest("t_ref", true);
 }
 
 }  // namespace