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

ash/wm/workspace/workspace_window_resizer.cc

 // 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.
 
 #include "ash/wm/workspace/workspace_window_resizer.h"
 
 #include <algorithm>
 #include <cmath>
 
 #include "ash/shell.h"
@@ skipping 42 matching lines @@
     aura::Window* window,
     const gfx::Point& location,
     int window_component,
     int grid_size,
     const std::vector<aura::Window*>& attached_windows) {
   Details details(window, location, window_component, grid_size);
   return details.is_resizable ?
       new WorkspaceWindowResizer(details, attached_windows) : NULL;
 }
 
-void WorkspaceWindowResizer::Drag(const gfx::Point& location) {
-  gfx::Rect bounds = CalculateBoundsForDrag(details_, location);
+void WorkspaceWindowResizer::Drag(const gfx::Point& location, int event_flags) {
+  bool disable_snap_to_grid = event_flags & ui::EF_CONTROL_DOWN ? true : false;
+  gfx::Rect bounds =
+      CalculateBoundsForDrag(details_, location, disable_snap_to_grid);
+
   if (wm::IsWindowNormal(details_.window))
     AdjustBoundsForMainWindow(&bounds);
   if (bounds != details_.window->bounds()) {
     if (!did_move_or_resize_)
       RestackWindows();
     did_move_or_resize_ = true;
   }
   UpdatePhantomWindow(location, bounds);
   if (!attached_windows_.empty())
     LayoutAttachedWindows(bounds);
@@ skipping 340 matching lines @@
   gfx::Rect area(gfx::Screen::GetMonitorAreaNearestWindow(details_.window));
   if (location.x() <= area.x())
     return SNAP_LEFT_EDGE;
   if (location.x() >= area.right() - 1)
     return SNAP_RIGHT_EDGE;
   return SNAP_NONE;
 }
 
 }  // namespace internal
 }  // namespace ash