a11y: Exclude children of nested keyboard accessible controls from a11y tree.

ui/views/view.h

Index: ui/views/view.h
diff --git a/ui/views/view.h b/ui/views/view.h
index 147785c6a86b255dc5e279a35c33d7bb0b7aa76b..11f6917e1ee0dd92bdc6a78afd7a8df7a891e78f 100644
--- a/ui/views/view.h
+++ b/ui/views/view.h
@@ -795,7 +795,8 @@ class VIEWS_EXPORT View : public ui::LayerDelegate,
   // IMPORTANT NOTE: loops in the focus hierarchy are not supported.
   void SetNextFocusableView(View* view);
 
-  // Sets |focus_behavior| and advances focus if necessary.
+  // Gets/sets |focus_behavior|. SetFocusBehavior() advances focus if necessary.
+  FocusBehavior focus_behavior() const { return focus_behavior_; }
   void SetFocusBehavior(FocusBehavior focus_behavior);
 
   // Returns true if this view is focusable, |enabled_| and drawn.
@@ -1170,9 +1171,6 @@ class VIEWS_EXPORT View : public ui::LayerDelegate,
 
   // Focus ---------------------------------------------------------------------
 
-  // Returns last set focus behavior.
-  FocusBehavior focus_behavior() const { return focus_behavior_; }
-
   // Override to be notified when focus has changed either to or from this View.
   virtual void OnFocus();
   virtual void OnBlur();
@@ -1606,9 +1604,8 @@ class VIEWS_EXPORT View : public ui::LayerDelegate,
 
   // Accessibility -------------------------------------------------------------
 
-  // Belongs to this view, but it's reference-counted on some platforms
-  // so we can't use a scoped_ptr. It's dereferenced in the destructor.
-  NativeViewAccessibility* native_view_accessibility_;
+  // The accessibility element used to represent this View.
+  std::unique_ptr<NativeViewAccessibility> native_view_accessibility_;
 
   // Observers -------------------------------------------------------------