Revert of Ensure that the focus ring in the bookmarks bar does not paint outside the parent view.

ui/views/controls/scroll_view.h

Index: ui/views/controls/scroll_view.h
diff --git a/ui/views/controls/scroll_view.h b/ui/views/controls/scroll_view.h
index 0dea574a81bc1462a0f209c771f7514c570fc1f6..af9111a05cae1a2dd25daba64afe629560c7751e 100644
--- a/ui/views/controls/scroll_view.h
+++ b/ui/views/controls/scroll_view.h
@@ -17,8 +17,6 @@
 }
 
 namespace views {
-class ViewObserverTest;
-
 namespace test {
 class ScrollViewTestApi;
 }
@@ -107,9 +105,6 @@
   void OnGestureEvent(ui::GestureEvent* event) override;
   const char* GetClassName() const override;
   void OnNativeThemeChanged(const ui::NativeTheme* theme) override;
-  void ViewHierarchyChanged(
-      const ViewHierarchyChangedDetails& details) override;
-  void OnChildLayerChanged(View* child) override;
 
   // ScrollBarController overrides:
   void ScrollToPosition(ScrollBar* source, int position) override;
@@ -123,7 +118,6 @@
 
  private:
   friend class test::ScrollViewTestApi;
-  FRIEND_TEST_ALL_PREFIXES(ViewObserverTest, ScrollViewChildAddLayerTest);
 
   class Viewport;
 
@@ -168,11 +162,6 @@
   void AddBorder();
   void UpdateBorder();
 
-  // Enables view port layering if |child| or any of its descendants has a
-  // layer. Returns true if yes. We short circuit the recursion if we enabled
-  // layering.
-  bool EnableLayeringRecursivelyForChild(View* child);
-
   // The current contents and its viewport. |contents_| is contained in
   // |contents_viewport_|.
   View* contents_;
@@ -214,12 +203,6 @@
 
   // Focus ring, if one is installed.
   View* focus_ring_ = nullptr;
-
-  // Set to true if we enabled layering for the viewport.
-  bool viewport_layer_enabled_ = false;
-
-  // Set to true if the scroll with layers feature is enabled.
-  const bool scroll_with_layers_enabled_;
 
   DISALLOW_COPY_AND_ASSIGN(ScrollView);
 };