Refactor accessible focus ring code so the layers are animation observers.

chrome/browser/chromeos/ui/accessibility_focus_ring_controller.h

Index: chrome/browser/chromeos/ui/accessibility_focus_ring_controller.h
diff --git a/chrome/browser/chromeos/ui/accessibility_focus_ring_controller.h b/chrome/browser/chromeos/ui/accessibility_focus_ring_controller.h
index 6c300e7015eb3cb712540597ba0b0e4ee6cfbdbe..d482bc628fa5c9b0b7d9771a01d4da93598a9531 100644
--- a/chrome/browser/chromeos/ui/accessibility_focus_ring_controller.h
+++ b/chrome/browser/chromeos/ui/accessibility_focus_ring_controller.h
@@ -13,20 +13,13 @@
 #include "base/time/time.h"
 #include "chrome/browser/chromeos/ui/accessibility_cursor_ring_layer.h"
 #include "chrome/browser/chromeos/ui/accessibility_focus_ring_layer.h"
-#include "ui/compositor/compositor_animation_observer.h"
 #include "ui/gfx/geometry/rect.h"
 
-namespace ui {
-class Compositor;
-}
-
 namespace chromeos {
 
 // AccessibilityFocusRingController handles drawing custom rings around
 // the focused object, cursor, and/or caret for accessibility.
-class AccessibilityFocusRingController
-    : public FocusRingLayerDelegate,
-      public ui::CompositorAnimationObserver {
+class AccessibilityFocusRingController : public FocusRingLayerDelegate {
  public:
   // Get the single instance of this class.
   static AccessibilityFocusRingController* GetInstance();
@@ -56,12 +49,9 @@ class AccessibilityFocusRingController
   virtual int GetMargin() const;
 
  private:
-  // FocusRingLayerDelegate.
+  // FocusRingLayerDelegate overrides.
   void OnDeviceScaleFactorChanged() override;
-
-  // CompositorAnimationObserver.
   void OnAnimationStep(base::TimeTicks timestamp) override;
-  void OnCompositingShuttingDown(ui::Compositor* compositor) override;
 
   void Update();
 
@@ -76,23 +66,18 @@ class AccessibilityFocusRingController
       gfx::Rect* middle,
       gfx::Rect* bottom) const;
   bool Intersects(const gfx::Rect& r1, const gfx::Rect& r2) const;
-  ui::Compositor* CompositorForBounds(const gfx::Rect& bounds);
-  void RemoveAnimationObservers();
-  void AddAnimationObservers();
 
   std::vector<gfx::Rect> rects_;
   std::vector<AccessibilityFocusRing> previous_rings_;
   std::vector<AccessibilityFocusRing> rings_;
   ScopedVector<AccessibilityFocusRingLayer> layers_;
   base::TimeTicks focus_change_time_;
-  ui::Compositor* compositor_;
 
   base::TimeTicks cursor_start_time_;
   base::TimeTicks cursor_change_time_;
   gfx::Point cursor_location_;
   float cursor_opacity_;
   std::unique_ptr<AccessibilityCursorRingLayer> cursor_layer_;
-  ui::Compositor* cursor_compositor_;
 
   gfx::Point caret_location_;
   std::unique_ptr<AccessibilityCursorRingLayer> caret_layer_;