Moves couple of WmShell methods to standalone functions

ash/common/wm/panels/panel_layout_manager.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/common/wm/panels/panel_layout_manager.h"
 
 #include <algorithm>
 #include <map>
 #include <utility>
 
@@ skipping 649 matching lines @@
     gfx::Rect icon_bounds = shelf_->GetScreenBoundsOfItemIconForWindow(panel);
 
     // If both the icon width and height are 0 then there is no icon in the
     // shelf. If the shelf is hidden, one of the height or width will be
     // 0 but the position in the shelf and major dimension is still reported
     // correctly and the panel can be aligned above where the hidden icon is.
     if (icon_bounds.width() == 0 && icon_bounds.height() == 0)
       continue;
 
     if (panel->IsFocused() ||
-        panel->Contains(panel->GetShell()->GetFocusedWindow())) {
+        panel->Contains(WmWindow::Get(wm::GetFocusedWindow()))) {
       DCHECK(!active_panel);
       active_panel = panel;
     }
     icon_bounds = panel_container_->ConvertRectFromScreen(icon_bounds);
     gfx::Point icon_origin = icon_bounds.origin();
     VisiblePanelPositionInfo position_info;
     int icon_start = horizontal ? icon_origin.x() : icon_origin.y();
     int icon_end =
         icon_start + (horizontal ? icon_bounds.width() : icon_bounds.height());
     position_info.major_length =
@@ skipping 261 matching lines @@
   // This bounds change will have caused a change to the Shelf which does not
   // propogate automatically to this class, so manually recalculate bounds.
   OnWindowResized();
 }
 
 void PanelLayoutManager::OnKeyboardClosed() {
   keyboard_observer_.RemoveAll();
 }
 
 }  // namespace ash