Build fix. Make overriding methods virtual to satisfy clang.

ui/views/bubble/bubble_border_2.h

 // Copyright (c) 2012 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.
 
 #ifndef UI_VIEWS_BUBBLE_BUBBLE_BORDER_2_H_
 #define UI_VIEWS_BUBBLE_BUBBLE_BORDER_2_H_
 
 #include "base/basictypes.h"
 #include "base/compiler_specific.h"
 #include "ui/gfx/shadow_value.h"
@@ skipping 29 matching lines @@
 
   void set_arrow_height(int arrow_height) { arrow_height_ = arrow_height; }
   int arrow_height() const { return arrow_height_; }
 
   void set_arrow_width(int arrow_width) { arrow_width_ = arrow_width; }
   int arrow_width() const { return arrow_width_; }
 
   void SetShadow(gfx::ShadowValue shadow);
 
   // views::BubbleBorder overrides:
-  int GetBorderThickness() const OVERRIDE;
+  virtual int GetBorderThickness() const OVERRIDE;
 
  protected:
   void PaintBackground(gfx::Canvas* canvas,
                        const gfx::Rect& bounds) const;
 
  private:
   // Gets arrow offset based on arrow location and |offset_|.
   int GetArrowOffset() const;
 
   // views::BubbleBorder overrides:
   virtual void GetInsets(gfx::Insets* insets) const OVERRIDE;
   virtual gfx::Rect GetBounds(const gfx::Rect& position_relative_to,
                               const gfx::Size& contents_size) const OVERRIDE;
-  void GetInsetsForArrowLocation(gfx::Insets* insets,
-                                 ArrowLocation arrow_loc) const OVERRIDE;
+  virtual void GetInsetsForArrowLocation(
+      gfx::Insets* insets,
+      ArrowLocation arrow_loc) const OVERRIDE;
 
   // views::Border overrides:
   virtual void Paint(const View& view,
                      gfx::Canvas* canvas) const OVERRIDE;
 
   int corner_radius_;
   int border_size_;
   int arrow_height_;
   int arrow_width_;
   SkColor background_color_;
   SkColor border_color_;
 
   // Offset in pixels by which the arrow is shifted relative the default middle
   // position. If the arrow is placed horizontally (at top or bottom), the |x_|
   // component of |offset_| specifies the offset, else, the |y_| component.
   gfx::Point offset_;
 
   gfx::ShadowValues shadows_;
 
   DISALLOW_COPY_AND_ASSIGN(BubbleBorder2);
 };
 
 }  // namespace views
 
 #endif  // UI_VIEWS_BUBBLE_BUBBLE_BORDER_2_H_