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..3e2e09443a45f57ac3d537614b04d4a1b6d61c69 100644
--- a/ui/base/resource/resource_bundle.h
+++ b/ui/base/resource/resource_bundle.h
@@ -256,6 +256,12 @@ class UI_BASE_EXPORT ResourceBundle {
   // Returns SCALE_FACTOR_100P if no resource is loaded.
   ScaleFactor GetMaxScaleFactor() const;
 
+ // 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.
+ // |scale_factor| contains the loaded scale factor for the image.
+ static float PlatformGetImageScale(ui::ScaleFactor scale_factor);

[sky, 2014/03/26 13:45:37]

This name is wordy (it was before, but when private it wasn't as much an issue).
How about GetScaleForImages()?

[ananta, 2014/03/26 19:40:10]

Removed this function. Moved this logic to ui::GetImageScale as per your
suggestion. Makes things simpler. I added a new function in layout.cc
GetImageScaleForScaleFactor which retains the old behavior. This is called from
resource_bundle.cc when images are being loaded.

+
  private:
   FRIEND_TEST_ALL_PREFIXES(ResourceBundleTest, DelegateGetPathForLocalePack);
   FRIEND_TEST_ALL_PREFIXES(ResourceBundleTest, DelegateGetImageNamed);
@@ -363,11 +369,6 @@ 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_;