chromeos: converts WindowResizer to aura::Window

ash/wm/window_resizer.h

Index: ash/wm/window_resizer.h
diff --git a/ash/wm/window_resizer.h b/ash/wm/window_resizer.h
index d0d8d8bb0b6cff574769288c6e938168c4dcd9f6..4ae6bdd30885913d985c9d78e5d01a1ca3f28d3e 100644
--- a/ash/wm/window_resizer.h
+++ b/ash/wm/window_resizer.h
@@ -13,14 +13,16 @@
 #include "base/macros.h"
 #include "ui/wm/public/window_move_client.h"
 
+namespace aura {
+class Window;
+}
+
 namespace gfx {
 class Rect;
 }
 
 namespace ash {
 
-class WmWindow;
-
 // WindowResizer is used by ToplevelWindowEventFilter to handle dragging, moving
 // or resizing a window. All coordinates passed to this are in the parent
 // windows coordinates.
@@ -57,9 +59,8 @@ class ASH_EXPORT WindowResizer {
   virtual void RevertDrag() = 0;
 
   // Returns the target window the resizer was created for.
-  WmWindow* GetTarget() const {
-    return window_state_ ? window_state_->window() : nullptr;
-  }
+  aura::Window* GetTarget() const;
+
   // See comment for |DragDetails::initial_location_in_parent|.
   const gfx::Point& GetInitialLocation() const {
     return window_state_->drag_details()->initial_location_in_parent;
@@ -100,7 +101,7 @@ class ASH_EXPORT WindowResizer {
 // Creates a WindowResizer for |window|. Returns a unique_ptr with null if
 // |window| should not be resized nor dragged.
 ASH_EXPORT std::unique_ptr<WindowResizer> CreateWindowResizer(
-    WmWindow* window,
+    aura::Window* window,
     const gfx::Point& point_in_parent,
     int window_component,
     aura::client::WindowMoveSource source);