chromeos: convert more ash/wm code to aura::Window

ash/wm/window_util.h

Index: ash/wm/window_util.h
diff --git a/ash/wm/window_util.h b/ash/wm/window_util.h
index 27c8d5d652759f939207f3a8fc604b71821e0bc8..d1b95504b2dd98662e2040255ae282347ea2acf9 100644
--- a/ash/wm/window_util.h
+++ b/ash/wm/window_util.h
@@ -15,6 +15,10 @@ namespace aura {
 class Window;
 }
 
+namespace gfx {
+class Point;
+}
+
 namespace ui {
 class Event;
 }
@@ -67,6 +71,11 @@ ASH_EXPORT void SnapWindowToPixelBoundary(aura::Window* window);
 ASH_EXPORT void SetSnapsChildrenToPhysicalPixelBoundary(
     aura::Window* container);
 
+// Convenience for window->delegate()->GetNonClientComponent(location) that
+// returns HTNOWHERE if window->delegate() is null.
+ASH_EXPORT int GetNonClientComponent(aura::Window* window,
+                                     const gfx::Point& location);
+
 }  // namespace wm
 }  // namespace ash