Use a correct scale factor in app_list::CachedLabel

ui/app_list/views/cached_label.h

 // Copyright 2013 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_APP_LIST_VIEWS_CACHED_LABEL_H_
 #define UI_APP_LIST_VIEWS_CACHED_LABEL_H_
 
 #include "ui/gfx/image/image_skia.h"
 #include "ui/views/controls/label.h"
 #include "ui/views/view.h"
 
 namespace gfx {
 class Canvas;
 }
 
 namespace app_list {
 
 // Subclass of views::Label that caches the rendered text in an ImageSkia.
 class CachedLabel : public views::Label {
  public:
   CachedLabel();
 
   // Have the next call to OnPaint() update the backing image.
   void Invalidate() { needs_repaint_ = true; }
 
   // Calls the base label's OnPaint() to paint into a backing image.
   void PaintToBackingImage();
 
 #if defined(OS_WIN)
-  // views::View overrides.
+  // Overridden from views::View:
   virtual void OnPaint(gfx::Canvas* canvas) OVERRIDE;
 #endif
 
+  // Overridden from ui::LayerDelegate:
+  virtual void OnDeviceScaleFactorChanged(float device_scale_factor) OVERRIDE;
+
  private:
   bool needs_repaint_;
   gfx::ImageSkia image_;
 };
 
 }  // namespace app_list
 
 #endif  // UI_APP_LIST_VIEWS_CACHED_LABEL_H_