Standardize usage of virtual/override/final specifiers in ui/.

ui/views/widget/desktop_aura/desktop_drag_drop_client_aurax11_unittest.cc

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include <map>
 #include <vector>
 
 // Include views_test_base.h first because the definition of None in X.h
 // conflicts with the definition of None in gtest-type-util.h
 #include "ui/views/test/views_test_base.h"
@@ skipping 778 matching lines @@
     ++num_updates_;
     last_event_mouse_position_ = event.location();
     last_event_flags_ = event.flags();
     return ui::DragDropTypes::DRAG_COPY;
   }
 
   void OnDragExited() override {
     ++num_exits_;
   }
 
-  virtual int OnPerformDrop(const ui::DropTargetEvent& event) override {
+  int OnPerformDrop(const ui::DropTargetEvent& event) override {
     ++num_drops_;
     last_event_mouse_position_ = event.location();
     last_event_flags_ = event.flags();
     return ui::DragDropTypes::DRAG_COPY;
   }
 
   int num_enters_;
   int num_updates_;
   int num_exits_;
   int num_drops_;
@@ skipping 148 matching lines @@
 // the aura::client::DragDropDelegate is properly notified.
 TEST_F(DesktopDragDropClientAuraX11ChromeSourceTargetTest, CtrlPressed) {
   base::MessageLoop::current()->PostTask(
       FROM_HERE,
       base::Bind(&ChromeSourceTargetStep2, client(), ui::EF_CONTROL_DOWN));
   int result = StartDragAndDrop();
   EXPECT_EQ(ui::DragDropTypes::DRAG_COPY, result);
 }
 
 }  // namespace views