Move WriteFile and WriteFileDescriptor from file_util to base namespace.

remoting/host/config_file_watcher_unittest.cc

Index: remoting/host/config_file_watcher_unittest.cc
diff --git a/remoting/host/config_file_watcher_unittest.cc b/remoting/host/config_file_watcher_unittest.cc
index 67b2e56ca08e72c5fd88e8c75e51e4165d0b8aa1..1a6217b3754034a714b5e350bb08ac5e3865f72a 100644
--- a/remoting/host/config_file_watcher_unittest.cc
+++ b/remoting/host/config_file_watcher_unittest.cc
@@ -96,7 +96,7 @@ void ConfigFileWatcherTest::TearDown() {
 // Verifies that the initial notification is delivered.
 TEST_F(ConfigFileWatcherTest, Basic) {
   std::string data("test");
-  EXPECT_NE(file_util::WriteFile(config_file_, data.c_str(),
+  EXPECT_NE(base::WriteFile(config_file_, data.c_str(),
                                  static_cast<int>(data.size())), -1);
 
   EXPECT_CALL(delegate_, OnConfigUpdated(_))
@@ -125,7 +125,7 @@ TEST_F(ConfigFileWatcherTest, Update) {
 
   // Modify the watched file.
   std::string data("test");
-  EXPECT_NE(file_util::WriteFile(config_file_, data.c_str(),
+  EXPECT_NE(base::WriteFile(config_file_, data.c_str(),
                                  static_cast<int>(data.size())), -1);
 
   run_loop_.Run();