Add virtual and OVERRIDE to base/ implementation files

base/time_unittest.cc

Index: base/time_unittest.cc
diff --git a/base/time_unittest.cc b/base/time_unittest.cc
index b81ef44bf40b464b2262026e3cbfbb283661bb88..9823147a33dac223d224726b3c988676cf8e7be6 100644
--- a/base/time_unittest.cc
+++ b/base/time_unittest.cc
@@ -2,10 +2,12 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
+#include "base/time.h"
+
 #include <time.h>
 
+#include "base/compiler_specific.h"
 #include "base/threading/platform_thread.h"
-#include "base/time.h"
 #include "build/build_config.h"
 #include "testing/gtest/include/gtest/gtest.h"
 
@@ -18,7 +20,7 @@ using base::TimeTicks;
 // See also pr_time_unittests.cc
 class TimeTest : public testing::Test {
  protected:
-  virtual void SetUp() {
+  virtual void SetUp() OVERRIDE {
     // Use mktime to get a time_t, and turn it into a PRTime by converting
     // seconds to microseconds.  Use 15th Oct 2007 12:45:00 local.  This
     // must be a time guaranteed to be outside of a DST fallback hour in