Standardize usage of virtual/override/final specifiers.

extensions/renderer/api/serial/data_sender_unittest.cc

Index: extensions/renderer/api/serial/data_sender_unittest.cc
diff --git a/extensions/renderer/api/serial/data_sender_unittest.cc b/extensions/renderer/api/serial/data_sender_unittest.cc
index 77dcfe169b8ee70a0c6f86dcaf355168b0333586..eac7e41c65a96639956a3b9391640621fcc7799f 100644
--- a/extensions/renderer/api/serial/data_sender_unittest.cc
+++ b/extensions/renderer/api/serial/data_sender_unittest.cc
@@ -16,7 +16,7 @@ class DataSenderTest : public ApiTestBase {
  public:
   DataSenderTest() {}
 
-  virtual void SetUp() override {
+  void SetUp() override {
     ApiTestBase::SetUp();
     env()->RegisterModule("async_waiter", IDR_ASYNC_WAITER_JS);
     env()->RegisterModule("data_sender", IDR_DATA_SENDER_JS);
@@ -28,7 +28,7 @@ class DataSenderTest : public ApiTestBase {
         base::Bind(&DataSenderTest::CreateDataSink, base::Unretained(this)));
   }
 
-  virtual void TearDown() override {
+  void TearDown() override {
     if (receiver_.get()) {
       receiver_->ShutDown();
       receiver_ = NULL;