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

ui/views/accessibility/native_view_accessibility_auralinux.cc

 // Copyright 2015 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.
 
 #include "ui/views/accessibility/native_view_accessibility_auralinux.h"
 
 #include <algorithm>
 #include <vector>
 
 #include "base/macros.h"
@@ skipping 84 matching lines @@
   }
 
   gfx::NativeViewAccessible HitTestSync(int x, int y) override {
     return nullptr;
   }
 
   gfx::NativeViewAccessible GetFocus() override {
     return nullptr;
   }
 
+  bool IsIgnored() override { return false; }
+
   gfx::AcceleratedWidget GetTargetForNativeAccessibilityEvent() override {
     return gfx::kNullAcceleratedWidget;
   }
 
   void DoDefaultAction() override {
   }
 
   bool SetStringValue(const base::string16& new_value) override {
     return false;
   }
@@ skipping 50 matching lines @@
 }
 
 gfx::NativeViewAccessible NativeViewAccessibilityAuraLinux::GetParent() {
   gfx::NativeViewAccessible parent = NativeViewAccessibility::GetParent();
   if (!parent)
     parent = AuraLinuxApplication::GetInstance()->GetNativeViewAccessible();
   return parent;
 }
 
 }  // namespace views