Explicitly show and hide accessible rings rather than using offscreen coords.

chrome/browser/chromeos/ui/accessibility_focus_ring_controller.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 CHROME_BROWSER_CHROMEOS_UI_ACCESSIBILITY_FOCUS_RING_CONTROLLER_H_
 #define CHROME_BROWSER_CHROMEOS_UI_ACCESSIBILITY_FOCUS_RING_CONTROLLER_H_
 
 #include <vector>
 
 #include "base/macros.h"
@@ skipping 13 matching lines @@
   // Get the single instance of this class.
   static AccessibilityFocusRingController* GetInstance();
 
   enum FocusRingBehavior { FADE_OUT_FOCUS_RING, PERSIST_FOCUS_RING };
 
   // Draw a focus ring around the given set of rects, in global screen
   // coordinates. Use |focus_ring_behavior| to specify whether the focus
   // ring should persist or fade out.
   void SetFocusRing(const std::vector<gfx::Rect>& rects,
                     FocusRingBehavior focus_ring_behavior);
+  void HideFocusRing();
 
   // Draw a ring around the mouse cursor. It fades out automatically.
   void SetCursorRing(const gfx::Point& location);
+  void HideCursorRing();
 
   // Draw a ring around the text caret. It fades out automatically.
   void SetCaretRing(const gfx::Point& location);
+  void HideCaretRing();
 
   // Don't fade in / out, for testing.
   void SetNoFadeForTesting();
 
  protected:
   AccessibilityFocusRingController();
   ~AccessibilityFocusRingController() override;
 
   // Given an unordered vector of bounding rectangles that cover everything
   // that currently has focus, populate a vector of one or more
@@ skipping 53 matching lines @@
   std::unique_ptr<AccessibilityCursorRingLayer> caret_layer_;
 
   friend struct base::DefaultSingletonTraits<AccessibilityFocusRingController>;
 
   DISALLOW_COPY_AND_ASSIGN(AccessibilityFocusRingController);
 };
 
 }  // namespace chromeos
 
 #endif  // CHROME_BROWSER_CHROMEOS_UI_ACCESSIBILITY_FOCUS_RING_CONTROLLER_H_