Move shadow code to views\corewm

ash/wm/resize_shadow.h

Index: ash/wm/resize_shadow.h
===================================================================
--- ash/wm/resize_shadow.h	(revision 167460)
+++ ash/wm/resize_shadow.h	(working copy)
@@ -17,12 +17,15 @@
 namespace ui {
 class Layer;
 }
+namespace views {
+namespace corewm {
+class ImageGrid;
+}
+}
 
 namespace ash {
 namespace internal {
 
-class ImageGrid;
-
 // A class to render the resize edge effect when the user moves their mouse
 // over a sizing edge.  This is just a visual effect; the actual resize is
 // handled by the EventFilter.
@@ -46,7 +49,7 @@
 
  private:
   // Images for the shadow effect.
-  scoped_ptr<ImageGrid> image_grid_;
+  scoped_ptr<views::corewm::ImageGrid> image_grid_;
 
   // Hit test value from last call to ShowForHitTest().  Used to prevent
   // repeatedly triggering the same animations for the same hit.