Ignore visibility when checking whether Position is editable or not at DeletetSelectionCommand

Source/core/editing/htmlediting.h

 /*
  * Copyright (C) 2004, 2006, 2008 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 126 matching lines @@
     return editingIgnoresContent(node) ? positionBeforeNode(node) : firstPositionInNode(node);
 }
 
 inline Position lastPositionInOrAfterNode(Node* node)
 {
     if (!node)
         return Position();
     return editingIgnoresContent(node) ? positionAfterNode(node) : lastPositionInNode(node);
 }
 
+Position lastEditablePositionBeforePositionInRoot(const Position&, Node*);
+
 // comparision functions on Position
 
 int comparePositions(const Position&, const Position&);
 int comparePositions(const PositionWithAffinity&, const PositionWithAffinity&);
 
 // boolean functions on Position
 
 enum EUpdateStyle { UpdateStyle, DoNotUpdateStyle };
 // FIXME: Both isEditablePosition and isRichlyEditablePosition rely on up-to-date
 // style to give proper results. They shouldn't update style by default, but
@@ skipping 101 matching lines @@
     // FIXME: this is required until 6853027 is fixed and text checking can do this for us.
     return character == '\'' || character == rightSingleQuotationMark || character == hebrewPunctuationGershayim;
 }
 
 String stringWithRebalancedWhitespace(const String&, bool startIsStartOfParagraph, bool endIsEndOfParagraph);
 const String& nonBreakingSpaceString();
 
 }
 
 #endif