Large Cursor: Add the toggle menuitem to a11y menu in uber tray

ash/shell/shell_delegate_impl.h

Index: ash/shell/shell_delegate_impl.h
diff --git a/ash/shell/shell_delegate_impl.h b/ash/shell/shell_delegate_impl.h
index 014e48c0a636cc66d219406595b5c78d749f3559..c01b201ebd9e297dce299f13b01d502fa4256dd1 100644
--- a/ash/shell/shell_delegate_impl.h
+++ b/ash/shell/shell_delegate_impl.h
@@ -54,6 +54,8 @@ class ShellDelegateImpl : public ash::ShellDelegate {
   virtual void SetMagnifierType(MagnifierType type) OVERRIDE;
   virtual bool IsMagnifierEnabled() const OVERRIDE;
   virtual MagnifierType GetMagnifierType() const OVERRIDE;
+  virtual void SetLargeCursorEnabled(bool enabled) OVERRIDE;
+  virtual bool IsLargeCursorEnabled() const OVERRIDE;
   virtual bool ShouldAlwaysShowAccessibilityMenu() const OVERRIDE;
   virtual void SilenceSpokenFeedback() const OVERRIDE;
   virtual app_list::AppListViewDelegate* CreateAppListViewDelegate() OVERRIDE;
@@ -89,6 +91,7 @@ class ShellDelegateImpl : public ash::ShellDelegate {
   bool high_contrast_enabled_;
   bool screen_magnifier_enabled_;
   MagnifierType screen_magnifier_type_;
+  bool large_cursor_enabled_;
 
   DISALLOW_COPY_AND_ASSIGN(ShellDelegateImpl);
 };