Add inlineOverflow and blockOverflow methods to NGFragment.

third_party/WebKit/Source/core/layout/ng/NGFragment.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 NGFragment_h
 #define NGFragment_h
 
 #include "core/CoreExport.h"
 #include "platform/LayoutUnit.h"
+#include "platform/heap/Handle.h"
+#include "wtf/Vector.h"
 
 namespace blink {
 
-class CORE_EXPORT NGFragment final {
+class CORE_EXPORT NGFragment final : public GarbageCollected<NGFragment> {
 public:
-    NGFragment(LayoutUnit inlineSize, LayoutUnit blockSize);
-    ~NGFragment() { }
+    NGFragment(LayoutUnit inlineSize, LayoutUnit blockSize,
+        LayoutUnit inlineOverflow, LayoutUnit blockOverflow);
 
+    // Returns the border-box size.
     LayoutUnit inlineSize() const { return m_inlineSize; }
     LayoutUnit blockSize() const { return m_blockSize; }
 
+    // Returns the total size, including the contents outside of the border-box.
+    LayoutUnit inlineOverflow() const { return m_inlineOverflow; }
+    LayoutUnit blockOverflow() const { return m_blockOverflow; }
+
+    // Returns the offset relative to the parent fragement's content-box.
     LayoutUnit inlineOffset() const { return m_inlineOffset; }
     LayoutUnit blockOffset() const { return m_blockOffset; }
 
+    // Should only be used by the parent fragement's layout.
     void setOffset(LayoutUnit inlineOffset, LayoutUnit blockOffset);
 
+    DECLARE_TRACE();
+
 private:
     LayoutUnit m_inlineSize;
     LayoutUnit m_blockSize;
 
+    LayoutUnit m_inlineOverflow;
+    LayoutUnit m_blockOverflow;
+
     LayoutUnit m_inlineOffset;
     LayoutUnit m_blockOffset;
+
+    HeapVector<Member<const NGFragment>> m_children;
 };
 
 } // namespace blink
 
 #endif // NGFragment_h