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

BUG=417463
[email protected]

Review URL: https://codereview.chromium.org/648653003

Cr-Commit-Position: refs/heads/master@{#300440}
diff --git a/chrome/browser/font_family_cache.h b/chrome/browser/font_family_cache.h
index e05f515..d5ff699 100644
--- a/chrome/browser/font_family_cache.h
+++ b/chrome/browser/font_family_cache.h
@@ -27,7 +27,7 @@
                         public content::NotificationObserver {
  public:
   explicit FontFamilyCache(Profile* profile);
-  virtual ~FontFamilyCache();
+  ~FontFamilyCache() override;
 
   // Gets or creates the relevant FontFamilyCache, and then fills |map|.
   static void FillFontFamilyMap(Profile* profile,
@@ -72,9 +72,9 @@
 
   // content::NotificationObserver override.
   // Called when the profile is being destructed.
-  virtual void Observe(int type,
-                       const content::NotificationSource& source,
-                       const content::NotificationDetails& details) override;
+  void Observe(int type,
+               const content::NotificationSource& source,
+               const content::NotificationDetails& details) override;
 
   // Cache of font family preferences.
   FontFamilyMap font_family_map_;