Remove the compile time flag for DATALIST Element.

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 20 matching lines @@
     [Reflect] attribute boolean disabled;
     readonly attribute HTMLFormElement form;
     attribute FileList files;
     [Reflect, URL] attribute DOMString formAction;
     [TreatNullAs=NullString] attribute DOMString formEnctype;
     [TreatNullAs=NullString] attribute DOMString formMethod;
     [Reflect] attribute boolean formNoValidate;
     [Reflect] attribute DOMString formTarget;
     attribute unsigned long height;
     attribute boolean indeterminate;
-    [Conditional=DATALIST_ELEMENT] readonly attribute HTMLElement list;
+    [EnabledAtRuntime=DataListElement] readonly attribute HTMLElement list;
     [Reflect] attribute DOMString max;
     [SetterRaisesException] attribute long maxLength;
     [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;
     [SetterRaisesException] attribute unsigned long size; // Changed string -> long -> unsigned long
@@ skipping 38 matching lines @@
     [Reflect, EnabledAtRuntime=directoryUpload] attribute boolean webkitdirectory;
     [Reflect] attribute DOMString useMap;
     [Reflect] attribute boolean incremental;
     [Conditional=INPUT_SPEECH, Reflect, EnabledAtRuntime=speechInput] attribute boolean webkitSpeech;
     [Conditional=INPUT_SPEECH, Reflect, EnabledAtRuntime=speechInput] attribute boolean webkitGrammar;
     [Conditional=INPUT_SPEECH, NotEnumerable] attribute EventListener onwebkitspeechchange;
 
     // See http://www.w3.org/TR/html-media-capture/
     [Conditional=MEDIA_CAPTURE] attribute DOMString capture;
 };