Remove unused feature HTMLAppletElementLegacyCall

Source/core/html/HTMLAppletElement.idl

 /*
  * Copyright (C) 2006, 2007, 2009, 2010 Apple Inc. All rights reserved.
  * Copyright (C) 2006 Samuel Weinig <sam.weinig@gmail.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
  * version 2 of the License, or (at your option) any later version.
  *
  * This library is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  * Library General Public License for more details.
  *
  * You should have received a copy of the GNU Library General Public License
  * along with this library; see the file COPYING.LIB.  If not, write to
  * the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
  * Boston, MA 02110-1301, USA.
  */
 
-[
-    Custom=LegacyCallAsFunction,
-] interface HTMLAppletElement : HTMLElement {
+interface HTMLAppletElement : HTMLElement {
     [Reflect] attribute DOMString align;
     [Reflect] attribute DOMString alt;
     [Reflect] attribute DOMString archive;
     [Reflect] attribute DOMString code;
     [Reflect, URL] attribute DOMString codeBase;
     [Reflect] attribute DOMString height;
     [Reflect] attribute unsigned long hspace;
     [Reflect] attribute DOMString name;
     [Reflect, URL] attribute DOMString _object;  // "object" is a reserved word
     [Reflect] attribute unsigned long vspace;
     [Reflect] attribute DOMString width;
     [Custom, NotEnumerable] getter boolean (unsigned long index);
     [Custom] setter boolean (unsigned long index, Node value);
     [Custom, NotEnumerable] getter Node (DOMString name);
     [Custom] setter Node (DOMString name, Node value);
 };