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

ash/wm/window_util.cc

Index: ash/wm/window_util.cc
diff --git a/ash/wm/window_util.cc b/ash/wm/window_util.cc
index e2d5a21061aacdf11d70a80c2d4d1dbd2fa290ea..7cca039a79d2175be63685cdac7c358e38b0ad82 100644
--- a/ash/wm/window_util.cc
+++ b/ash/wm/window_util.cc
@@ -21,6 +21,7 @@
 #include "ui/aura/window.h"
 #include "ui/aura/window_delegate.h"
 #include "ui/aura/window_event_dispatcher.h"
+#include "ui/base/hit_test.h"
 #include "ui/compositor/dip_util.h"
 #include "ui/gfx/geometry/rect.h"
 #include "ui/gfx/geometry/size.h"
@@ -134,5 +135,11 @@ void SetSnapsChildrenToPhysicalPixelBoundary(aura::Window* container) {
   container->SetProperty(kSnapChildrenToPixelBoundary, true);
 }
 
+int GetNonClientComponent(aura::Window* window, const gfx::Point& location) {
+  return window->delegate()
+             ? window->delegate()->GetNonClientComponent(location)
+             : HTNOWHERE;
+}
+
 }  // namespace wm
 }  // namespace ash