Introdcue AshWindowTreeHost and move ash/chrome specific code in WTH to ash.

ui/aura/window_tree_host_win.h

Index: ui/aura/window_tree_host_win.h
diff --git a/ui/aura/window_tree_host_win.h b/ui/aura/window_tree_host_win.h
index 1d2f2560dc24f8bd5785891b259151fadec51955..dc5f46cf8b87e6dbef7ccd9d19d9a4632b171400 100644
--- a/ui/aura/window_tree_host_win.h
+++ b/ui/aura/window_tree_host_win.h
@@ -13,27 +13,22 @@
 
 namespace aura {
 
-class WindowTreeHostWin : public WindowTreeHost,
-                          public ui::EventSource,
-                          public gfx::WindowImpl {
+class AURA_EXPORT WindowTreeHostWin : public WindowTreeHost,
+                                      public ui::EventSource,
+                                      public gfx::WindowImpl {
  public:
-  WindowTreeHostWin(const gfx::Rect& bounds);
+  explicit WindowTreeHostWin(const gfx::Rect& bounds);
   virtual ~WindowTreeHostWin();
   // WindowTreeHost:
   virtual gfx::AcceleratedWidget GetAcceleratedWidget() OVERRIDE;
   virtual void Show() OVERRIDE;
   virtual void Hide() OVERRIDE;
-  virtual void ToggleFullScreen() OVERRIDE;
   virtual gfx::Rect GetBounds() const OVERRIDE;
   virtual void SetBounds(const gfx::Rect& bounds) OVERRIDE;
-  virtual gfx::Insets GetInsets() const OVERRIDE;
-  virtual void SetInsets(const gfx::Insets& insets) OVERRIDE;
   virtual gfx::Point GetLocationOnNativeScreen() const OVERRIDE;
   virtual void SetCapture() OVERRIDE;
   virtual void ReleaseCapture() OVERRIDE;
   virtual bool QueryMouseLocation(gfx::Point* location_return) OVERRIDE;
-  virtual bool ConfineCursorToRootWindow() OVERRIDE;
-  virtual void UnConfineCursor() OVERRIDE;
   virtual void SetCursorNative(gfx::NativeCursor cursor) OVERRIDE;
   virtual void MoveCursorToNative(const gfx::Point& location) OVERRIDE;
   virtual void OnCursorVisibilityChangedNative(bool show) OVERRIDE;
@@ -79,11 +74,7 @@ class WindowTreeHostWin : public WindowTreeHost,
   void OnPaint(HDC dc);
   void OnSize(UINT param, const gfx::Size& size);
 
-  bool fullscreen_;
   bool has_capture_;
-  RECT saved_window_rect_;
-  DWORD saved_window_style_;
-  DWORD saved_window_ex_style_;
 
   DISALLOW_COPY_AND_ASSIGN(WindowTreeHostWin);
 };