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

chrome/browser/ui/webui/about_ui.cc

Index: chrome/browser/ui/webui/about_ui.cc
diff --git a/chrome/browser/ui/webui/about_ui.cc b/chrome/browser/ui/webui/about_ui.cc
index 88073ef620d095a10ed04ddfcc1054a160995272..1ea4ee47d9c243042999f6ad708927889a6dc09d 100644
--- a/chrome/browser/ui/webui/about_ui.cc
+++ b/chrome/browser/ui/webui/about_ui.cc
@@ -125,10 +125,10 @@ class AboutMemoryHandler : public MemoryDetails {
       : callback_(callback) {
   }
 
-  virtual void OnDetailsAvailable() override;
+  void OnDetailsAvailable() override;
 
  private:
-  virtual ~AboutMemoryHandler() {}
+  ~AboutMemoryHandler() override {}
 
   void BindProcessMetrics(base::DictionaryValue* data,
                           ProcessMemoryInformation* info);