Standardize usage of virtual/override/final in components/

components/dom_distiller/core/distilled_page_prefs_unittests.cc

Index: components/dom_distiller/core/distilled_page_prefs_unittests.cc
diff --git a/components/dom_distiller/core/distilled_page_prefs_unittests.cc b/components/dom_distiller/core/distilled_page_prefs_unittests.cc
index 665fbc94f10b70e36e4bb7d94607955f99cee973..cf13fce10a219e6561b75d367f9c1c94e401aad4 100644
--- a/components/dom_distiller/core/distilled_page_prefs_unittests.cc
+++ b/components/dom_distiller/core/distilled_page_prefs_unittests.cc
@@ -19,14 +19,13 @@ class TestingObserver : public DistilledPagePrefs::Observer {
       : font_(DistilledPagePrefs::SANS_SERIF),
         theme_(DistilledPagePrefs::LIGHT) {}
 
-  virtual void OnChangeFontFamily(
-      DistilledPagePrefs::FontFamily new_font) override {
+  void OnChangeFontFamily(DistilledPagePrefs::FontFamily new_font) override {
     font_ = new_font;
   }
 
   DistilledPagePrefs::FontFamily GetFontFamily() { return font_; }
 
-  virtual void OnChangeTheme(DistilledPagePrefs::Theme new_theme) override {
+  void OnChangeTheme(DistilledPagePrefs::Theme new_theme) override {
     theme_ = new_theme;
   }