Remove dead markup serialization code.

sky/engine/core/editing/Editor.cpp

 /*
  * Copyright (C) 2006, 2007, 2008, 2011 Apple Inc. All rights reserved.
  * Copyright (C) 2008 Nokia Corporation and/or its subsidiary(-ies)
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
@@ skipping 27 matching lines @@
 #include "sky/engine/core/dom/Text.h"
 #include "sky/engine/core/editing/DeleteSelectionCommand.h"
 #include "sky/engine/core/editing/InputMethodController.h"
 #include "sky/engine/core/editing/RenderedPosition.h"
 #include "sky/engine/core/editing/ReplaceSelectionCommand.h"
 #include "sky/engine/core/editing/SpellChecker.h"
 #include "sky/engine/core/editing/TypingCommand.h"
 #include "sky/engine/core/editing/UndoStack.h"
 #include "sky/engine/core/editing/VisibleUnits.h"
 #include "sky/engine/core/editing/htmlediting.h"
-#include "sky/engine/core/editing/markup.h"
 #include "sky/engine/core/events/KeyboardEvent.h"
 #include "sky/engine/core/events/ScopedEventQueue.h"
 #include "sky/engine/core/events/TextEvent.h"
 #include "sky/engine/core/fetch/ImageResource.h"
 #include "sky/engine/core/fetch/ResourceFetcher.h"
 #include "sky/engine/core/frame/FrameView.h"
 #include "sky/engine/core/frame/LocalFrame.h"
 #include "sky/engine/core/frame/Settings.h"
 #include "sky/engine/core/frame/UseCounter.h"
 #include "sky/engine/core/html/HTMLCanvasElement.h"
@@ skipping 786 matching lines @@
     return m_frame.spellChecker();
 }
 
 void Editor::toggleOverwriteModeEnabled()
 {
     m_overwriteModeEnabled = !m_overwriteModeEnabled;
     frame().selection().setShouldShowBlockCursor(m_overwriteModeEnabled);
 }
 
 } // namespace blink