Implement autocapitalize in Blink to be used by the embedder.

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.
  *
  * 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.
  */
 
 // https://html.spec.whatwg.org/#htmlinputelement
 
 interface HTMLInputElement : HTMLElement {
     [Reflect] attribute DOMString accept;
     [Reflect] attribute DOMString alt;
+    attribute DOMString autocapitalize;
     [Reflect] attribute DOMString autocomplete;
     [Reflect] attribute boolean autofocus;
     [Reflect=checked] attribute boolean defaultChecked;
     attribute boolean checked;
     [Reflect] attribute DOMString dirName;
     [Reflect] attribute boolean disabled;
     [ImplementedAs=formOwner] readonly attribute HTMLFormElement? form;
     // The 'files' attribute is intentionally not readonly.
     // https://www.w3.org/Bugs/Public/show_bug.cgi?id=22682
     attribute FileList? files;
@@ skipping 64 matching lines @@
     [Reflect] attribute DOMString useMap;
 
     // HTML Media Capture
     // http://www.w3.org/TR/html-media-capture/
     [RuntimeEnabled=MediaCapture, Reflect] attribute boolean capture;
 
     // Non-standard APIs
     [Reflect, MeasureAs=PrefixedDirectoryAttribute] attribute boolean webkitdirectory;
     [Reflect, MeasureAs=IncrementalAttribute] attribute boolean incremental;
 };