Use RelocatablePosition in CompositeEditCommand::moveParagraphs

third_party/WebKit/Source/core/editing/RelocatablePosition.cpp

+// 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.
+
+#include "core/editing/RelocatablePosition.h"
+
+namespace blink {
+
+RelocatablePosition::RelocatablePosition()
+    : m_range(nullptr)

[yosin_UTC9, 2016/07/06 06:50:30]

You don't need to initialize |Member<Range>|

+{
+}
+
+RelocatablePosition::RelocatablePosition(const Position& position)
+    : m_range(position.isNotNull() ? Range::create(*position.document(), position, position) : nullptr)
+{
+}
+
+RelocatablePosition::~RelocatablePosition()
+{
+    if (m_range)

[yosin_UTC9, 2016/07/06 06:50:30]

We prefer early-return style.

+        m_range->dispose();
+}
+
+Position RelocatablePosition::position() const
+{
+    if (!m_range)
+        return Position();
+    DCHECK(m_range->collapsed());
+    return m_range->startPosition();
+}
+
+} // namespace blink