Implement minlength for <input> and <textarea>.

Source/core/html/HTMLInputElement.idl

 /*
  * Copyright (C) 2006, 2010 Apple Inc. All rights reserved.
  * Copyright (C) 2006 Samuel Weinig <sam.weinig@gmail.com>
  * Copyright (C) 2012 Samsung Electronics. 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
  * version 2 of the License, or (at your option) any later version.
  *
@@ skipping 28 matching lines @@
     [CustomElementCallbacks] attribute DOMString formEnctype;
     [CustomElementCallbacks] attribute DOMString formMethod;
     [Reflect] attribute boolean formNoValidate;
     [Reflect] attribute DOMString formTarget;
     [CustomElementCallbacks] attribute unsigned long height;
     attribute boolean indeterminate;
     [RuntimeEnabled=InputModeAttribute, Reflect] attribute DOMString inputMode;
     readonly attribute HTMLElement list;
     [Reflect] attribute DOMString max;
     [RaisesException=Setter, CustomElementCallbacks] attribute long maxLength;
+    [RaisesException=Setter, CustomElementCallbacks] attribute long minLength;
     [Reflect] attribute DOMString min;
     [Reflect] attribute boolean multiple;
     [Reflect] attribute DOMString name;
     [Reflect] attribute DOMString pattern;
     [Reflect] attribute DOMString placeholder;
     [Reflect] attribute boolean readOnly;
     [Reflect] attribute boolean required;
     [RaisesException=Setter, CustomElementCallbacks] attribute unsigned long size; // Changed string -> long -> unsigned long
     [Reflect, URL] attribute DOMString src;
     [Reflect] attribute DOMString step;
@@ skipping 33 matching lines @@
                            [Default=Undefined] optional long end,
                            optional DOMString direction);
 
     // Non-standard attributes
     [Reflect, MeasureAs=PrefixedDirectoryAttribute] attribute boolean webkitdirectory;
     [Reflect, MeasureAs=IncrementalAttribute] attribute boolean incremental;
 
     // See http://www.w3.org/TR/html-media-capture/
     [RuntimeEnabled=MediaCapture, Reflect] attribute boolean capture;
 };