Convert first letter into a pseudo element.

Source/core/dom/Position.cpp

 /*
  * Copyright (C) 2004, 2005, 2006, 2009 Apple Inc. All rights reserved.
  *
  * 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
  *    notice, this list of conditions and the following disclaimer in the
@@ skipping 67 matching lines @@
     }
     return 0;
 }
 
 Position::Position(PassRefPtrWillBeRawPtr<Node> anchorNode, LegacyEditingOffset offset)
     : m_anchorNode(anchorNode)
     , m_offset(offset.value())
     , m_anchorType(anchorTypeForLegacyEditingPosition(m_anchorNode.get(), m_offset))
     , m_isLegacyEditingPosition(true)
 {
-    ASSERT(!m_anchorNode || !m_anchorNode->isPseudoElement());
+    ASSERT(!m_anchorNode || !m_anchorNode->isPseudoElement() || m_anchorNode->isFirstLetterPseudoElement());
 }
 
 Position::Position(PassRefPtrWillBeRawPtr<Node> anchorNode, AnchorType anchorType)
     : m_anchorNode(anchorNode)
     , m_offset(0)
     , m_anchorType(anchorType)
     , m_isLegacyEditingPosition(false)
 {
-    ASSERT(!m_anchorNode || !m_anchorNode->isPseudoElement());
+    ASSERT(!m_anchorNode || !m_anchorNode->isPseudoElement() || m_anchorNode->isFirstLetterPseudoElement());
 
     ASSERT(anchorType != PositionIsOffsetInAnchor);
     ASSERT(!((anchorType == PositionIsBeforeChildren || anchorType == PositionIsAfterChildren)
         && (m_anchorNode->isTextNode() || editingIgnoresContent(m_anchorNode.get()))));
 }
 
 Position::Position(PassRefPtrWillBeRawPtr<Node> anchorNode, int offset, AnchorType anchorType)
     : m_anchorNode(anchorNode)
     , m_offset(offset)
     , m_anchorType(anchorType)
     , m_isLegacyEditingPosition(false)
 {
-    ASSERT(!m_anchorNode || !m_anchorNode->isPseudoElement());
+    ASSERT(!m_anchorNode || !m_anchorNode->isPseudoElement() || m_anchorNode->isFirstLetterPseudoElement());
 
     ASSERT(anchorType == PositionIsOffsetInAnchor);
 }
 
 Position::Position(PassRefPtrWillBeRawPtr<Text> textNode, unsigned offset)
     : m_anchorNode(textNode)
     , m_offset(static_cast<int>(offset))
     , m_anchorType(PositionIsOffsetInAnchor)
     , m_isLegacyEditingPosition(false)
 {
@@ skipping 1185 matching lines @@
     pos.showTreeForThis();
 }
 
 void showTree(const blink::Position* pos)
 {
     if (pos)
         pos->showTreeForThis();
 }
 
 #endif