Standardize usage of virtual/override/final specifiers.

chrome/browser/ui/views/infobars/extension_infobar.cc

Index: chrome/browser/ui/views/infobars/extension_infobar.cc
diff --git a/chrome/browser/ui/views/infobars/extension_infobar.cc b/chrome/browser/ui/views/infobars/extension_infobar.cc
index 89a8547f891c6e253f2dbf4d6f628d853c9f706d..92d665be28d5738ea7796c113093c8b2368201bf 100644
--- a/chrome/browser/ui/views/infobars/extension_infobar.cc
+++ b/chrome/browser/ui/views/infobars/extension_infobar.cc
@@ -52,11 +52,10 @@ class MenuImageSource: public gfx::CanvasImageSource {
         drop_image_(drop_image) {
   }
 
-  virtual ~MenuImageSource() {
-  }
+  ~MenuImageSource() override {}
 
   // Overridden from gfx::CanvasImageSource
-  virtual void Draw(gfx::Canvas* canvas) override {
+  void Draw(gfx::Canvas* canvas) override {
     int image_size = extension_misc::EXTENSION_ICON_BITTY;
     canvas->DrawImageInt(icon_, 0, 0, icon_.width(), icon_.height(), 0, 0,
                          image_size, image_size, false);