Standardize usage of virtual/override/final in chrome/

chrome/test/base/test_browser_window.cc

Index: chrome/test/base/test_browser_window.cc
diff --git a/chrome/test/base/test_browser_window.cc b/chrome/test/base/test_browser_window.cc
index e295b3b24817214302d5fb061a672f0e5cb313fe..da54513dc48f0da016d54c6be9714c058f077cea 100644
--- a/chrome/test/base/test_browser_window.cc
+++ b/chrome/test/base/test_browser_window.cc
@@ -22,13 +22,11 @@ class TestBrowserWindowOwner : public chrome::BrowserListObserver {
   explicit TestBrowserWindowOwner(TestBrowserWindow* window) : window_(window) {
     BrowserList::AddObserver(this);
   }
-  virtual ~TestBrowserWindowOwner() {
-    BrowserList::RemoveObserver(this);
-  }
+  ~TestBrowserWindowOwner() override { BrowserList::RemoveObserver(this); }
 
  private:
   // Overridden from BrowserListObserver:
-  virtual void OnBrowserRemoved(Browser* browser) override {
+  void OnBrowserRemoved(Browser* browser) override {
     if (browser->window() == window_.get())
       delete this;
   }