[LayoutNG] Initial implementation of NGBoxIterator

third_party/WebKit/Source/core/layout/ng/ng_box_iterator.h

+// Copyright 2016 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.
+
+#ifndef NGBoxIterator_h
+#define NGBoxIterator_h
+
+#include "core/layout/LayoutObject.h"
+
+namespace blink {
+
+class NGBox;
+
+// NG Box iterator over siblings of the layout object.
+class NGBoxIterator {
+ public:
+  explicit NGBoxIterator(const LayoutObject*);
+  NGBox first();
+  NGBox next();
+
+ private:
+  void reset();
+
+  const LayoutObject* m_layoutObject;
+  const LayoutObject* m_currentChild;
+};
+
+}  // namespace blink
+#endif  // NGBoxIterator_h