Remove some unused functions in core

Source/core/layout/style/AppliedTextDecoration.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/layout/style/AppliedTextDecoration.h"
 
 namespace blink {
 
 AppliedTextDecoration::AppliedTextDecoration(TextDecoration line, TextDecorationStyle style, StyleColor color)
     : m_line(line)
     , m_style(style)
     , m_color(color)
 {
 }
 
 AppliedTextDecoration::AppliedTextDecoration(TextDecoration line)
     : m_line(line)
     , m_style(TextDecorationStyleSolid)
     , m_color(StyleColor::currentColor())
 {
 }
 
-AppliedTextDecoration::AppliedTextDecoration()
-    : m_line(TextDecorationUnderline)
-    , m_style(TextDecorationStyleSolid)
-    , m_color(StyleColor::currentColor())
-{
-}
-
 bool AppliedTextDecoration::operator==(const AppliedTextDecoration& o) const
 {
     return m_color == o.m_color && m_line == o.m_line && m_style == o.m_style;
 }
 
 } // namespace blink