Standardize usage of virtual/override/final in content/browser/

content/browser/mach_broker_mac.h

Index: content/browser/mach_broker_mac.h
diff --git a/content/browser/mach_broker_mac.h b/content/browser/mach_broker_mac.h
index 2f2ab1372dc919fa6e107b896bd237ebc60ea6ea..9088ca70265491cc76ae9826c6ecc05c99fa4832 100644
--- a/content/browser/mach_broker_mac.h
+++ b/content/browser/mach_broker_mac.h
@@ -64,25 +64,25 @@ class CONTENT_EXPORT MachBroker : public base::ProcessMetrics::PortProvider,
   void AddPlaceholderForPid(base::ProcessHandle pid);
 
   // Implement |ProcessMetrics::PortProvider|.
-  virtual mach_port_t TaskForPid(base::ProcessHandle process) const override;
+  mach_port_t TaskForPid(base::ProcessHandle process) const override;
 
   // Implement |BrowserChildProcessObserver|.
-  virtual void BrowserChildProcessHostDisconnected(
-      const ChildProcessData& data) override;
-  virtual void BrowserChildProcessCrashed(
+  void BrowserChildProcessHostDisconnected(
       const ChildProcessData& data) override;
+  void BrowserChildProcessCrashed(const ChildProcessData& data) override;
 
   // Implement |NotificationObserver|.
-  virtual void Observe(int type,
-                       const NotificationSource& source,
-                       const NotificationDetails& details) override;
+  void Observe(int type,
+               const NotificationSource& source,
+               const NotificationDetails& details) override;
+
  private:
   friend class MachBrokerTest;
   friend class MachListenerThreadDelegate;
   friend struct DefaultSingletonTraits<MachBroker>;
 
   MachBroker();
-  virtual ~MachBroker();
+  ~MachBroker() override;
 
   // Updates the mapping for |pid| to include the given |mach_info|.  Does
   // nothing if PlaceholderForPid() has not already been called for the given