Standardize usage of virtual/override/final in chrome/browser/media

chrome/browser/media/midi_permission_context_factory.h

Index: chrome/browser/media/midi_permission_context_factory.h
diff --git a/chrome/browser/media/midi_permission_context_factory.h b/chrome/browser/media/midi_permission_context_factory.h
index 61305dc5370e7aba6bb44a18563f747e0304ba29..53edae6bf97202e6ff00aebf6384008b787550c1 100644
--- a/chrome/browser/media/midi_permission_context_factory.h
+++ b/chrome/browser/media/midi_permission_context_factory.h
@@ -21,12 +21,12 @@ class MidiPermissionContextFactory
   friend struct DefaultSingletonTraits<MidiPermissionContextFactory>;
 
   MidiPermissionContextFactory();
-  virtual ~MidiPermissionContextFactory();
+  ~MidiPermissionContextFactory() override;
 
   // BrowserContextKeyedBaseFactory methods:
-  virtual KeyedService* BuildServiceInstanceFor(
+  KeyedService* BuildServiceInstanceFor(
       content::BrowserContext* profile) const override;
-  virtual content::BrowserContext* GetBrowserContextToUse(
+  content::BrowserContext* GetBrowserContextToUse(
       content::BrowserContext* context) const override;
 
   DISALLOW_COPY_AND_ASSIGN(MidiPermissionContextFactory);