ALL-IN-ONE Introduce enum class TextAffinity

Source/core/editing/PositionWithAffinity.cpp

 // Copyright 2014 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 "config.h"
 #include "core/editing/PositionWithAffinity.h"
 
 namespace blink {
 
 template <typename Strategy>
-PositionWithAffinityTemplate<Strategy>::PositionWithAffinityTemplate(const PositionAlgorithm<Strategy>& position, EAffinity affinity)
+PositionWithAffinityTemplate<Strategy>::PositionWithAffinityTemplate(const PositionAlgorithm<Strategy>& position, TextAffinity affinity)
     : m_position(position)
     , m_affinity(affinity)
 {
 }
 
 template <typename Strategy>
 PositionWithAffinityTemplate<Strategy>::PositionWithAffinityTemplate()
-    : m_affinity(DOWNSTREAM)
+    : m_affinity(TextAffinity::Downstream)
 {
 }
 
 template <typename Strategy>
 PositionWithAffinityTemplate<Strategy>::~PositionWithAffinityTemplate()
 {
 }
 
 template <typename Strategy>
 bool PositionWithAffinityTemplate<Strategy>::operator==(const PositionWithAffinityTemplate& other) const
 {
     if (isNull())
         return other.isNull();
     return m_affinity == other.m_affinity && m_position == other.m_position;
 }
 
 template class CORE_TEMPLATE_EXPORT PositionWithAffinityTemplate<EditingStrategy>;
 template class CORE_TEMPLATE_EXPORT PositionWithAffinityTemplate<EditingInComposedTreeStrategy>;
 
 } // namespace blink