Allow the cursor to warp even when a window is dragged

ash/ui_controls_ash.cc

Index: ash/ui_controls_ash.cc
diff --git a/ash/ui_controls_ash.cc b/ash/ui_controls_ash.cc
index 6069c612b179ba60f51dc00b83f1a7f603c7b0b9..4c60c54c8149563adf8a010a3efe7fdbd4968c14 100644
--- a/ash/ui_controls_ash.cc
+++ b/ash/ui_controls_ash.cc
@@ -4,6 +4,7 @@
 
 #include "ash/shell.h"
 #include "ash/shell_factory.h"
+#include "ash/wm/coordinate_conversion.h"
 #include "ash/wm/window_properties.h"
 #include "ui/aura/root_window.h"
 #include "ui/aura/ui_controls_aura.h"
@@ -33,7 +34,7 @@ ui_controls::UIControlsAura* GetUIControlsForRootWindow(
 // absolute screen coordinates.  NULL if there is no RootWindow under the
 // |point|.
 ui_controls::UIControlsAura* GetUIControlsAt(const gfx::Point& point) {
-  aura::RootWindow* root = Shell::GetRootWindowAt(point);
+  aura::RootWindow* root = wm::GetRootWindowAt(point);
   return root ? GetUIControlsForRootWindow(root) : NULL;
 }