Enables HiDPI favicon to be displayed in tab strip on CrOS

ui/gfx/image/image_skia.h

Index: ui/gfx/image/image_skia.h
diff --git a/ui/gfx/image/image_skia.h b/ui/gfx/image/image_skia.h
index 38e6e7a57f674dba44ba47a1785abc07ec40ee40..a32ee9fa9a9634203d560be8756c5709e4a9e876 100644
--- a/ui/gfx/image/image_skia.h
+++ b/ui/gfx/image/image_skia.h
@@ -67,6 +67,10 @@ class UI_EXPORT ImageSkia {
 
   ~ImageSkia();
 
+  // Returns true if this object is backed by the same ImageSkiaStorage as
+  // |other|. Will also return true if both images are isNull().
+  bool BackedBySameObjectAs(const gfx::ImageSkia& other) const;
+
   // Adds |image_rep| to the image reps contained by this object.
   void AddRepresentation(const gfx::ImageSkiaRep& image_rep);