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

ash/wm/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_WINDOW_RESIZER_H_
 #define ASH_WM_WINDOW_RESIZER_H_
 #pragma once
 
 #include "ash/ash_export.h"
 #include "base/basictypes.h"
@@ skipping 30 matching lines @@
   // |grid_size|.
   static int AlignToGrid(int location, int grid_size);
 
   // Variant of AlignToGrid that rounds up.
   static int AlignToGridRoundUp(int location, int grid_size);
 
   // Variant of AlignToGrid that rounds down.
   static int AlignToGridRoundDown(int location, int grid_size);
 
   // Invoked to drag/move/resize the window. |location| is in the coordinates
-  // of the window supplied to the constructor.
-  virtual void Drag(const gfx::Point& location) = 0;
+  // of the window supplied to the constructor. |event_flags| is the event
+  // flags from mouse event.
+  virtual void Drag(const gfx::Point& location, int event_flags) = 0;
 
   // Invoked to complete the drag.
   virtual void CompleteDrag() = 0;
 
   // Reverts the drag.
   virtual void RevertDrag() = 0;
 
  protected:
   struct Details {
     Details();
@@ skipping 26 matching lines @@
 
     // Will the drag actually modify the window?
     bool is_resizable;
 
     // Size of the grid.
     int grid_size;
   };
 
   static gfx::Rect CalculateBoundsForDrag(
       const Details& details,
-      const gfx::Point& location);
+      const gfx::Point& location,
+      bool disable_snap_to_grid);
 
   static gfx::Rect AdjustBoundsToGrid(const gfx::Rect& bounds,
                                       int grid_size);
 
   static bool IsBottomEdge(int component);
 
  private:
   // Returns the new origin of the window. The arguments are the difference
   // between the current location and the initial location.
   static gfx::Point GetOriginForDrag(const Details& details,
                                      int delta_x,
                                      int delta_y);
 
   // Returns the size of the window for the drag.
   static gfx::Size GetSizeForDrag(const Details& details,
                                   int* delta_x,
-                                  int* delta_y);
+                                  int* delta_y,
+                                  bool disable_snap_to_grid);
 
   // Returns the width of the window.
   static int GetWidthForDrag(const Details& details,
                              int min_width,
-                             int* delta_x);
+                             int* delta_x,
+                             bool disable_snap_to_grid);
 
   // Returns the height of the drag.
   static int GetHeightForDrag(const Details& details,
                               int min_height,
-                              int* delta_y);
+                              int* delta_y,
+                              bool disable_snap_to_grid);
 };
 
 }  // namespace aura
 
 #endif  // ASH_WM_WINDOW_RESIZER_H_