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

ppapi/tests/test_flash_file.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 "ppapi/tests/test_flash_file.h"
 
 #include <algorithm>
 #include <vector>
 
 #include "ppapi/c/pp_file_info.h"
@@ skipping 267 matching lines @@
   std::string contents = "This is file.";
   PP_FileHandle file_handle = FileModuleLocal::OpenFile(instance_,
                                                         filename,
                                                         PP_FILEOPENFLAG_WRITE |
                                                         PP_FILEOPENFLAG_CREATE);
   ASSERT_NE(PP_kInvalidFileHandle, file_handle);
   ASSERT_TRUE(WriteFile(file_handle, contents));
   CloseFileHandle(file_handle);
   ASSERT_TRUE(FileModuleLocal::CreateDir(instance_, dirname));
 
-  ASSERT_TRUE(FileModuleLocal::GetDirContents(instance_, "", &result));
-  FileModuleLocal::DirEntry expected[] =
-    { {"..", true},
-      {filename, false},
-      {dirname, true}
-    };
+  ASSERT_TRUE(
+      FileModuleLocal::GetDirContents(instance_, std::string(), &result));
+  FileModuleLocal::DirEntry expected[] = { { "..", true }, { filename, false },
+                                           { dirname, true } };
   size_t expected_size = sizeof(expected) / sizeof(expected[0]);
 
   std::sort(expected, expected + expected_size, DirEntryLessThan);
   std::sort(result.begin(), result.end(), DirEntryLessThan);
 
   ASSERT_EQ(expected_size, result.size());
   ASSERT_TRUE(std::equal(expected, expected + expected_size, result.begin(),
                          DirEntryEqual));
 
   PASS();
@@ skipping 18 matching lines @@
   size_t after_close = 0;
   ASSERT_SUBTEST_SUCCESS(GetItemCountUnderModuleLocalRoot(&after_close));
   ASSERT_EQ(before_create, after_close);
 
   PASS();
 }
 
 std::string TestFlashFile::GetItemCountUnderModuleLocalRoot(
     size_t* item_count) {
   std::vector<FileModuleLocal::DirEntry> contents;
-  ASSERT_TRUE(FileModuleLocal::GetDirContents(instance_, "", &contents));
+  ASSERT_TRUE(
+      FileModuleLocal::GetDirContents(instance_, std::string(), &contents));
   *item_count = contents.size();
   PASS();
 }