Allow the cursor to warp even when a window is dragged

ash/wm/coordinate_conversion.h

Index: ash/wm/coordinate_conversion.h
diff --git a/ash/wm/coordinate_conversion.h b/ash/wm/coordinate_conversion.h
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index 0000000000000000000000000000000000000000..207afd4f63297d899ec4babc1d1fb4ba23ca7ee8
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+++ b/ash/wm/coordinate_conversion.h
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+// Copyright (c) 2012 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef ASH_WM_COORDINATE_CONVERSION_H_
+#define ASH_WM_COORDINATE_CONVERSION_H_
+
+#include "ash/ash_export.h"
+
+#include "ui/gfx/point.h"
+
+namespace aura {
+class RootWindow;
+class Window;
+}  // namespace gfx
+
+namespace gfx {
+class Rect;
+}  // namespace gfx
+
+namespace ash {
+namespace wm {
+
+// Returns the RootWindow at |point| in the virtual screen coordinates.
+// Returns NULL if the root window does not exist at the given
+// point.
+ASH_EXPORT aura::RootWindow* GetRootWindowAt(const gfx::Point& point);
+
+// Returns the RootWindow that shares the most area with |rect| in
+// the virtual scren coordinates.
+ASH_EXPORT aura::RootWindow* GetRootWindowMatching(const gfx::Rect& rect);
+
+// Finds the root window at |location| in |window|'s coordinates and returns a
+// pair of root window and location in that root window's coordinates. The
+// function usually returns |window->GetRootWindow()|, but if the mouse pointer
+// is moved outside the |window|'s root while the mouse is captured, it returns
+// the other root window.
+ASH_EXPORT std::pair<aura::RootWindow*, gfx::Point>
+GetRootWindowRelativeToWindow(aura::Window* window, const gfx::Point& location);
+
+// Converts the |point| from a given |window|'s coordinates into the screen
+// coordinates.
+ASH_EXPORT void ConvertPointToScreen(aura::Window* window, gfx::Point* point);
+
+// Converts the |point| from the screen coordinates to a given |window|'s
+// coordinates.
+ASH_EXPORT void ConvertPointFromScreen(aura::Window* window,
+                                       gfx::Point* point_in_screen);
+
+}  // namespace wm
+}  // namespace ash
+
+#endif  // ASH_WM_COORDINATE_CONVERSION_H_