Fix unsigned comparison in previousIfPositionIsAfterLineBreak

Source/core/html/HTMLTextFormControlElement.cpp

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 1999 Antti Koivisto (koivisto@kde.org)
  *           (C) 2001 Dirk Mueller (mueller@kde.org)
  * Copyright (C) 2004, 2005, 2006, 2007 Apple Inc. All rights reserved.
  *           (C) 2006 Alexey Proskuryakov (ap@nypop.com)
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Library General Public
  * License as published by the Free Software Foundation; either
@@ skipping 807 matching lines @@
         case Position::PositionIsAfterAnchor:
             return Position(position.anchorNode(), Position::PositionIsBeforeAnchor);
         case Position::PositionIsBeforeAnchor:
             return previousIfPositionIsAfterLineBreak(endOfPrevious(*position.anchorNode(), innerEditor), innerEditor);
         default:
             ASSERT_NOT_REACHED();
         }
     } else if (position.anchorNode()->isTextNode()) {
         Text* textNode = toText(position.anchorNode());
         unsigned offset = position.offsetInContainerNode();
-        if (textNode->length() == 0 || offset <= 0) {
+        if (textNode->length() == 0 || offset == 0) {
             return previousIfPositionIsAfterLineBreak(endOfPrevious(*position.anchorNode(), innerEditor), innerEditor);
         }
 
         if (offset <= textNode->length() && textNode->data()[offset - 1] == '\n') {
             return Position(textNode, offset - 1);
         }
     }
 
     return position;
 }
@@ skipping 62 matching lines @@
             Text* textNode = toText(node);
             size_t firstLineBreak = textNode->data().find('\n', isPivotNode ? pivotPosition.offsetInContainerNode() : 0);
             if (firstLineBreak != kNotFound)
                 return Position(textNode, firstLineBreak + 1);
         }
     }
     return endOfInnerText(textFormControl);
 }
 
 } // namespace Webcore