replace etc1_pixel_ref with skia version (SkMallocPixelRef)

cc/resources/ui_resource_bitmap.h

Index: cc/resources/ui_resource_bitmap.h
diff --git a/cc/resources/ui_resource_bitmap.h b/cc/resources/ui_resource_bitmap.h
index ea54f613b10d043f0afbdff8b592f88ff6bdb5fe..64e962cf8f0147e731514402422dd9202363a4ac 100644
--- a/cc/resources/ui_resource_bitmap.h
+++ b/cc/resources/ui_resource_bitmap.h
@@ -44,17 +44,14 @@ class CC_EXPORT UIResourceBitmap {
   // User must ensure that |skbitmap| is immutable.  The SkBitmap Format should
   // be 32-bit RGBA.
   explicit UIResourceBitmap(const SkBitmap& skbitmap);
-
-  UIResourceBitmap(const skia::RefPtr<ETC1PixelRef>& etc1_pixel_ref,
-                   gfx::Size size);
-
+  explicit UIResourceBitmap(const skia::RefPtr<SkPixelRef>& pixel_ref);
   ~UIResourceBitmap();
 
  private:
   friend class AutoLockUIResourceBitmap;
+
   void Create(const skia::RefPtr<SkPixelRef>& pixel_ref,
-              UIResourceFormat format,
-              gfx::Size size);
+              UIResourceFormat format);
 
   skia::RefPtr<SkPixelRef> pixel_ref_;
   UIResourceFormat format_;