TEST: Focus change between login screen and status area

ash/common/system/status_area_widget_delegate.h

Index: ash/common/system/status_area_widget_delegate.h
diff --git a/ash/common/system/status_area_widget_delegate.h b/ash/common/system/status_area_widget_delegate.h
index 915bff9017d27677aafc2ac72b666216e9ad6782..47ea699e36db008748eb2fac8516b629af881d72 100644
--- a/ash/common/system/status_area_widget_delegate.h
+++ b/ash/common/system/status_area_widget_delegate.h
@@ -33,8 +33,16 @@ class ASH_EXPORT StatusAreaWidgetDelegate : public views::AccessiblePaneView,
 
   void set_alignment(ShelfAlignment alignment) { alignment_ = alignment; }
 
+  void set_custom_focus_traversable(
+      views::FocusTraversable* custom_focus_traversable) {
+    custom_focus_traversable_ = custom_focus_traversable;
+  }
+
   // Overridden from views::AccessiblePaneView.
   View* GetDefaultFocusableChild() override;
+  views::FocusSearch* GetFocusSearch() override;
+  views::FocusTraversable* GetFocusTraversableParent() override;
+  views::View* GetFocusTraversableParentView() override;
 
   // Overridden from views::View:
   views::Widget* GetWidget() override;
@@ -60,6 +68,8 @@ class ASH_EXPORT StatusAreaWidgetDelegate : public views::AccessiblePaneView,
   // screen.
   void SetBorderOnChild(views::View* child, bool extend_border_to_edge);
 
+  views::FocusTraversable* custom_focus_traversable_ = nullptr;
+
   const FocusCycler* focus_cycler_for_testing_;
 
   // TODO(jamescook): Get this from WmShelf.