Add virtual and OVERRIDE to base/ implementation files

base/tools_sanity_unittest.cc

Index: base/tools_sanity_unittest.cc
diff --git a/base/tools_sanity_unittest.cc b/base/tools_sanity_unittest.cc
index 60ac015af5c251e9c3d36ec2e814f70a86a53ed8..64da1bec9136ecf78606fcc20377dbdc85b14faa 100644
--- a/base/tools_sanity_unittest.cc
+++ b/base/tools_sanity_unittest.cc
@@ -163,8 +163,8 @@ namespace {
 class TOOLS_SANITY_TEST_CONCURRENT_THREAD : public PlatformThread::Delegate {
  public:
   explicit TOOLS_SANITY_TEST_CONCURRENT_THREAD(bool *value) : value_(value) {}
-  ~TOOLS_SANITY_TEST_CONCURRENT_THREAD() {}
-  void ThreadMain() {
+  virtual ~TOOLS_SANITY_TEST_CONCURRENT_THREAD() {}
+  virtual void ThreadMain() OVERRIDE {
     *value_ = true;
 
     // Sleep for a few milliseconds so the two threads are more likely to live
@@ -179,8 +179,8 @@ class TOOLS_SANITY_TEST_CONCURRENT_THREAD : public PlatformThread::Delegate {
 class ReleaseStoreThread : public PlatformThread::Delegate {
  public:
   explicit ReleaseStoreThread(base::subtle::Atomic32 *value) : value_(value) {}
-  ~ReleaseStoreThread() {}
-  void ThreadMain() {
+  virtual ~ReleaseStoreThread() {}
+  virtual void ThreadMain() OVERRIDE {
     base::subtle::Release_Store(value_, kMagicValue);
 
     // Sleep for a few milliseconds so the two threads are more likely to live
@@ -195,8 +195,8 @@ class ReleaseStoreThread : public PlatformThread::Delegate {
 class AcquireLoadThread : public PlatformThread::Delegate {
  public:
   explicit AcquireLoadThread(base::subtle::Atomic32 *value) : value_(value) {}
-  ~AcquireLoadThread() {}
-  void ThreadMain() {
+  virtual ~AcquireLoadThread() {}
+  virtual void ThreadMain() OVERRIDE {
     // Wait for the other thread to make Release_Store
     PlatformThread::Sleep(TimeDelta::FromMilliseconds(100));
     base::subtle::Acquire_Load(value_);