Update StickyKeys overlay to show or hide AltGr depending on the

ash/sticky_keys/sticky_keys_overlay.h

 // Copyright 2014 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.
 
 #ifndef ASH_STICKY_KEYS_STICKY_KEYS_OVERLAY_H_
 #define ASH_STICKY_KEYS_STICKY_KEYS_OVERLAY_H_
 
 #include "ash/ash_export.h"
 #include "ash/sticky_keys/sticky_keys_state.h"
 #include "base/memory/scoped_ptr.h"
@@ skipping 18 matching lines @@
 // a transparent window on the top left of the screen, showing the state of
 // each sticky key modifier.
 class ASH_EXPORT StickyKeysOverlay : public ui::LayerAnimationObserver {
  public:
   StickyKeysOverlay();
   virtual ~StickyKeysOverlay();
 
   // Shows or hides the overlay.
   void Show(bool visible);
 
+  void SetModifiersVisible(bool mod3_visible, bool altgr_visible);

[Tim Song, 2014/03/05 19:22:27]

It doesn't hurt to make this generic as it's possible to disable ctrl, alt, and
shift through the keyboard settings, and one day we might want to update the UI
to reflect this.

[Zachary Kuznia, 2014/03/05 21:12:30]

Done.

+
   // Updates the overlay with the current state of a sticky key modifier.
   void SetModifierKeyState(ui::EventFlags modifier,
                            StickyKeyState state);
 
   // Get the current state of the sticky key modifier in the overlay.
   StickyKeyState GetModifierKeyState(ui::EventFlags modifier);
 
   // Returns true if the overlay is currently visible. If the overlay is
   // animating, the returned value is the target of the animation.
   bool is_visible() { return is_visible_; }
@@ skipping 13 matching lines @@
   bool is_visible_;
   scoped_ptr<views::Widget> overlay_widget_;
   // Ownership of |overlay_view_| is passed to the view heirarchy.
   StickyKeysOverlayView* overlay_view_;
   gfx::Size widget_size_;
 };
 
 }  // namespace ash
 
 #endif  // ASH_STICKY_KEYS_STICKY_KEYS_OVERLAY_H_