replace OVERRIDE and FINAL with override and final in chrome/browser/[a-i]*

chrome/browser/chrome_browser_main_posix.cc

Index: chrome/browser/chrome_browser_main_posix.cc
diff --git a/chrome/browser/chrome_browser_main_posix.cc b/chrome/browser/chrome_browser_main_posix.cc
index 691e8b3f20726d7e9af382e06a8b9227aee43d44..43927f66508cd037f487c1497da1f5768afb995b 100644
--- a/chrome/browser/chrome_browser_main_posix.cc
+++ b/chrome/browser/chrome_browser_main_posix.cc
@@ -97,7 +97,7 @@ class ExitHandler : public content::NotificationObserver {
   // Overridden from content::NotificationObserver:
   virtual void Observe(int type,
                        const content::NotificationSource& source,
-                       const content::NotificationDetails& details) OVERRIDE;
+                       const content::NotificationDetails& details) override;
 
  private:
   ExitHandler();
@@ -158,7 +158,7 @@ class ShutdownDetector : public base::PlatformThread::Delegate {
  public:
   explicit ShutdownDetector(int shutdown_fd);
 
-  virtual void ThreadMain() OVERRIDE;
+  virtual void ThreadMain() override;
 
  private:
   const int shutdown_fd_;