Ensure that extension resources are loaded with the correct scaling applied on Windows.

ui/base/resource/resource_bundle.h

Index: ui/base/resource/resource_bundle.h
diff --git a/ui/base/resource/resource_bundle.h b/ui/base/resource/resource_bundle.h
index 8b63aa777d30e250fe7e4f4478c39ea7331447aa..93b50ea7177af1add84ea455fcbbe8cc3d323071 100644
--- a/ui/base/resource/resource_bundle.h
+++ b/ui/base/resource/resource_bundle.h
@@ -363,11 +363,6 @@ class UI_BASE_EXPORT ResourceBundle {
                                     float loaded_image_scale,
                                     float desired_scale);
 
- // Returns the scale to be used for loading an image. In all platforms except
- // windows this is based on the scale factors of the loaded resource packs.
- // On Windows this returns the device scale factor if high dpi is enabled.
- float PlatformGetImageScale();
-
   // This pointer is guaranteed to outlive the ResourceBundle instance and may
   // be NULL.
   Delegate* delegate_;