Standardize usage of virtual/override/final specifiers.

ash/ime/mode_indicator_view.cc

Index: ash/ime/mode_indicator_view.cc
diff --git a/ash/ime/mode_indicator_view.cc b/ash/ime/mode_indicator_view.cc
index 9c16b560f831079909cf7267b5af3bbabb3a4bd2..c8df071a759eb4cc5e0aa11d1032f78292c9eb89 100644
--- a/ash/ime/mode_indicator_view.cc
+++ b/ash/ime/mode_indicator_view.cc
@@ -28,11 +28,11 @@ class ModeIndicatorFrameView : public views::BubbleFrameView {
  public:
   explicit ModeIndicatorFrameView(const gfx::Insets& content_margins)
       : views::BubbleFrameView(content_margins) {}
-  virtual ~ModeIndicatorFrameView() {}
+  ~ModeIndicatorFrameView() override {}
 
  private:
   // views::BubbleFrameView overrides:
-  virtual gfx::Rect GetAvailableScreenBounds(const gfx::Rect& rect) override {
+  gfx::Rect GetAvailableScreenBounds(const gfx::Rect& rect) override {
     return gfx::Screen::GetNativeScreen()->GetDisplayNearestPoint(
         rect.CenterPoint()).bounds();
   }