Add ctrl+drag feature for allowing resizing window with exact positioning.

ash/wm/default_window_resizer.h

 // 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_DEFAULT_WINDOW_RESIZER_H_
 #define ASH_WM_DEFAULT_WINDOW_RESIZER_H_
 #pragma once
 
 #include "ash/wm/window_resizer.h"
 #include "base/compiler_specific.h"
 
 namespace ash {
 
 namespace internal {
 class RootWindowEventFilter;
 }
 
 // WindowResizer is used by ToplevelWindowEventFilter to handle dragging, moving
 // or resizing a window. All coordinates passed to this are in the parent
 // windows coordiantes.
 class ASH_EXPORT DefaultWindowResizer : public WindowResizer {
  public:
   virtual ~DefaultWindowResizer();
 
   // Creates a new DefaultWindowResizer. The caller takes ownership of the
   // returned object. Returns NULL if not resizable.
   static DefaultWindowResizer* Create(aura::Window* window,
                                       const gfx::Point& location,
-                                      int window_component,
-                                      int grid_size);
+                                      int window_component);
 
   // Returns true if the drag will result in changing the window in anyway.
   bool is_resizable() const { return details_.is_resizable; }
 
   bool changed_size() const {
     return !(details_.bounds_change & kBoundsChange_Repositions);
   }
   aura::Window* target_window() const { return details_.window; }
 
   // WindowResizer overides:
-  virtual void Drag(const gfx::Point& location) OVERRIDE;
-  virtual void CompleteDrag() OVERRIDE;
+  virtual void Drag(const gfx::Point& location, int event_flags) OVERRIDE;
+  virtual void CompleteDrag(int event_flags) OVERRIDE;
   virtual void RevertDrag() OVERRIDE;
 
  private:
   explicit DefaultWindowResizer(const Details& details);
 
   const Details details_;
 
   // Set to true once Drag() is invoked and the bounds of the window change.
   bool did_move_or_resize_;
 
   internal::RootWindowEventFilter* root_filter_;
 
   DISALLOW_COPY_AND_ASSIGN(DefaultWindowResizer);
 };
 
 }  // namespace aura
 
 #endif  // ASH_WM_DEFAULT_WINDOW_RESIZER_H_