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

ui/views/accessibility/native_view_accessibility_base.h

Index: ui/views/accessibility/native_view_accessibility_base.h
diff --git a/ui/views/accessibility/native_view_accessibility_base.h b/ui/views/accessibility/native_view_accessibility_base.h
index 0a5c09aa146960d26b66999c0f68ab4f3f6a14da..7cbe71dad3371a877074b8282e557ed476d413e9 100644
--- a/ui/views/accessibility/native_view_accessibility_base.h
+++ b/ui/views/accessibility/native_view_accessibility_base.h
@@ -20,6 +20,10 @@
 
 namespace views {
 
+namespace test {
+class NativeViewAccessibilityBaseIgnoredElementsTest;
+}
+
 class View;
 class Widget;
 
@@ -30,6 +34,9 @@ class VIEWS_EXPORT NativeViewAccessibilityBase
       public ui::AXPlatformNodeDelegate,
       public WidgetObserver {
  public:
+  // Convenience method for checking if a View should be ignored by a11y.
+  static bool IsIgnoredView(View* view);
+
   ~NativeViewAccessibilityBase() override;
 
   // NativeViewAccessibility:
@@ -59,8 +66,17 @@ class VIEWS_EXPORT NativeViewAccessibilityBase
   void SetParentWidget(Widget* parent_widget);
 
  protected:
+  friend class test::NativeViewAccessibilityBaseIgnoredElementsTest;
+
+  // Retrieves the NativeViewAccessibility instance for the given View. This
+  // invokes View::GetNativeViewAccessible() to ensure it exists.
+  static NativeViewAccessibilityBase* GetForView(View* view);
+
   explicit NativeViewAccessibilityBase(View* view);
 
+  // Retrieves the gfx::NativeViewAccessibility for |view_|'s Widget/Rootview.
+  virtual gfx::NativeViewAccessible GetNativeViewAccessibleForWidget();
+
   // Weak. Owns this.
   View* view_;
 
@@ -79,6 +95,7 @@ class VIEWS_EXPORT NativeViewAccessibilityBase
   // a scoped_ptr. It is dereferenced in the destructor.
   ui::AXPlatformNode* ax_node_;
 
+  // Accessibility information associated to |view_|.
   mutable ui::AXNodeData data_;
 
   DISALLOW_COPY_AND_ASSIGN(NativeViewAccessibilityBase);