Refactors DockedWindowLayoutManager in terms of ash/wm/common

ash/system/status_area_widget_delegate.h

Index: ash/system/status_area_widget_delegate.h
diff --git a/ash/system/status_area_widget_delegate.h b/ash/system/status_area_widget_delegate.h
index d14361f8e6eb821434d86ee6f10181c3337a382b..1ddd6d0851f5508392da87b593e7e1a31b346fda 100644
--- a/ash/system/status_area_widget_delegate.h
+++ b/ash/system/status_area_widget_delegate.h
@@ -31,7 +31,7 @@ class ASH_EXPORT StatusAreaWidgetDelegate : public views::AccessiblePaneView,
   // Sets the focus cycler.
   void SetFocusCyclerForTesting(const FocusCycler* focus_cycler);
 
-  void set_alignment(ShelfAlignment alignment) { alignment_ = alignment; }
+  void set_alignment(wm::ShelfAlignment alignment) { alignment_ = alignment; }
 
   // Overridden from views::AccessiblePaneView.
   View* GetDefaultFocusableChild() override;
@@ -56,7 +56,7 @@ class ASH_EXPORT StatusAreaWidgetDelegate : public views::AccessiblePaneView,
   void UpdateWidgetSize();
 
   const FocusCycler* focus_cycler_for_testing_;
-  ShelfAlignment alignment_;
+  wm::ShelfAlignment alignment_;
 
   ShelfGestureHandler gesture_handler_;