Make first-letter style to work with editing

Source/core/editing/InsertLineBreakCommand.cpp

 /*
  * Copyright (C) 2005, 2006 Apple Computer, 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 66 matching lines @@
         insertNodeBefore(node, pos.deprecatedNode());
 }
 
 // Whether we should insert a break element or a '\n'.
 bool InsertLineBreakCommand::shouldUseBreakElement(const Position& insertionPos)
 {
     // An editing position like [input, 0] actually refers to the position before
     // the input element, and in that case we need to check the input element's
     // parent's renderer.
     Position p(insertionPos.parentAnchoredEquivalent());
-    return p.deprecatedNode()->renderer() && !p.deprecatedNode()->renderer()->style()->preserveNewline();
+    return p.renderer() && !p.renderer()->style()->preserveNewline();
 }
 
 void InsertLineBreakCommand::doApply()
 {
     deleteSelection();
     VisibleSelection selection = endingSelection();
     if (!selection.isNonOrphanedCaretOrRange())
         return;
 
     VisiblePosition caret(selection.visibleStart());
@@ skipping 82 matching lines @@
         // before the line break (if the line break is at the end of a block it isn't selectable).
         // So, this next call sets the endingSelection() to a caret just after the line break
         // that we inserted, or just before it if it's at the end of a block.
         setEndingSelection(endingSelection().visibleEnd());
     }
 
     rebalanceWhitespace();
 }
 
 }