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

chrome/test/perf/page_cycler_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/basictypes.h"
 #include "base/command_line.h"
 #include "base/file_util.h"
 #include "base/files/file_path.h"
 #include "base/path_service.h"
 #include "base/process_util.h"
@@ skipping 197 matching lines @@
     pages->assign(UTF8ToWide(cookie));
     ASSERT_FALSE(pages->empty());
 
     // Wait for the report.html to be loaded.
     ASSERT_TRUE(WaitUntilCookieValue(
         tab.get(), test_url, "__navigated_to_report",
         TestTimeouts::action_max_timeout(), "1"));
 
     // Get the timing cookie value from the DOM automation.
     std::wstring wcookie;
-    ASSERT_TRUE(tab->ExecuteAndExtractString(L"",
-          L"window.domAutomationController.send("
-          L"JSON.stringify(__get_timings()));",
-          &wcookie));
+    ASSERT_TRUE(tab->ExecuteAndExtractString(
+        std::wstring(),
+        L"window.domAutomationController.send("
+        L"JSON.stringify(__get_timings()));",
+        &wcookie));
     cookie = base::SysWideToNativeMB(wcookie);
 
     // JSON.stringify() encapsulates the returned string in quotes, strip them.
     std::string::size_type start_idx = cookie.find("\"");
     std::string::size_type end_idx = cookie.find_last_of("\"");
     if (start_idx != std::string::npos &&
         end_idx != std::string::npos &&
         start_idx < end_idx) {
       cookie = cookie.substr(start_idx+1, end_idx-start_idx-1);
     }
@@ skipping 21 matching lines @@
       PrintIOPerfInfo(suffix);
       perf_test::PrintSystemCommitCharge(suffix, stop_size - start_size,
                                          false /* not important */);
       ASSERT_NO_FATAL_FAILURE(PrintMemoryHistograms());
     }
 
     std::string trace_name = "t" + std::string(suffix);
 
     printf("Pages: [%s]\n", base::SysWideToNativeMB(pages).c_str());
 
-    perf_test::PrintResultList(graph, "", trace_name, timings, "ms",
-                               true /* important */);
+    perf_test::PrintResultList(
+        graph, std::string(), trace_name, timings, "ms", true /* important */);
   }
 
   void RunTest(const char* graph, const char* name, bool use_http) {
     RunTestWithSuffix(graph, name, use_http, "");
   }
 
  private:
   void PrintMemoryHistogram(const std::string& name,
                             const std::string& units) {
     scoped_refptr<TabProxy> tab(GetActiveTab());
     ASSERT_TRUE(tab.get());
     std::wstring whistogram;
     ASSERT_TRUE(tab->ExecuteAndExtractString(
-        L"",
+        std::wstring(),
         L"window.domAutomationController.send("
         L"window.domAutomationController.getHistogram ? "
         L"window.domAutomationController.getHistogram(\"" +
         base::SysUTF8ToWide(name) + L"\") : '')",
         &whistogram));
     std::string histogram = base::SysWideToNativeMB(whistogram);
     printf("HISTOGRAM %s: %s = %s %s\n",
            name.c_str(), name.c_str(), histogram.c_str(), units.c_str());
   }
 
@@ skipping 388 matching lines @@
 TEST_F(PageCyclerAccessibilityTest, MozFileWithAccessibilityEnabled) {
   num_test_iterations_ = 1;
   RunTest("times", "moz", false);
 }
 
 TEST_F(PageCyclerAccessibilityTest, MorejsFileWithAccessibilityEnabled) {
   RunTest("times", "morejs", false);
 }
 
 }  // namespace