Snap widgets to pixel boundary on ash

ash/wm/window_state.h

 // Copyright 2013 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_STATE_H_
 #define ASH_WM_WINDOW_STATE_H_
 
 #include "ash/ash_export.h"
 #include "ash/wm/drag_details.h"
 #include "ash/wm/wm_types.h"
@@ skipping 312 matching lines @@
   // workspace if the window represented by |window_state| is side snapped.
   void AdjustSnappedBounds(gfx::Rect* bounds);
 
   // Updates the window show state according to the current window state type.
   // Note that this does not update the window bounds.
   void UpdateWindowShowStateFromStateType();
 
   void NotifyPreStateTypeChange(WindowStateType old_window_state_type);
   void NotifyPostStateTypeChange(WindowStateType old_window_state_type);
 
-  // Sets |bounds| as is.
+  // Sets |bounds| as is and ensure the layer is aligned with pixel boundary.
   void SetBoundsDirect(const gfx::Rect& bounds);
 
   // Sets the window's |bounds| with constraint where the size of the
   // new bounds will not exceeds the size of the work area.
   void SetBoundsConstrained(const gfx::Rect& bounds);
 
   // Sets the wndow's |bounds| and transitions to the new bounds with
   // a scale animation.
   void SetBoundsDirectAnimated(const gfx::Rect& bounds);
 
@@ skipping 44 matching lines @@
 ASH_EXPORT WindowState* GetWindowState(aura::Window* window);
 
 // const version of GetWindowState.
 ASH_EXPORT const WindowState*
 GetWindowState(const aura::Window* window);
 
 }  // namespace wm
 }  // namespace ash
 
 #endif  // ASH_WM_WINDOW_STATE_H_