Implement minlength for <input> and <textarea>.

Source/core/html/HTMLTextFormControlElement.h

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 1999 Antti Koivisto (koivisto@kde.org)
  *           (C) 2000 Dirk Mueller (mueller@kde.org)
  * Copyright (C) 2004, 2005, 2006, 2007, 2008, 2009, 2010 Apple Inc. All rights reserved.
  * Copyright (C) 2009, 2010, 2011 Google Inc. All rights reserved.
  *
  * 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 21 matching lines @@
 class ExceptionState;
 class Position;
 class Range;
 class VisiblePosition;
 
 enum TextFieldSelectionDirection { SelectionHasNoDirection, SelectionHasForwardDirection, SelectionHasBackwardDirection };
 enum TextFieldEventBehavior { DispatchNoEvent, DispatchChangeEvent, DispatchInputAndChangeEvent };
 
 class HTMLTextFormControlElement : public HTMLFormControlElementWithState {
 public:
-    // Common flag for HTMLInputElement::tooLong() and HTMLTextAreaElement::tooLong().
+    // Common flag for HTMLInputElement::tooLong(), HTMLTextAreaElement::tooLong(),
+    // HTMLInputElement::tooShort() and HTMLTextAreaElement::tooShort().
     enum NeedsToCheckDirtyFlag {CheckDirtyFlag, IgnoreDirtyFlag};
     // Option of setSelectionRange.
     enum SelectionOption {
         ChangeSelection,
         NotChangeSelection
     };
 
     virtual ~HTMLTextFormControlElement();
 
     void forwardEvent(Event*);
@@ skipping 103 matching lines @@
 }
 
 DEFINE_HTMLELEMENT_TYPE_CASTS_WITH_FUNCTION(HTMLTextFormControlElement);
 
 HTMLTextFormControlElement* enclosingTextFormControl(const Position&);
 HTMLTextFormControlElement* enclosingTextFormControl(Node*);
 
 } // namespace
 
 #endif