Adds support for the search key in the Virtual Keyboard.

ui/keyboard/resources/main.css

 /*
  Copyright (c) 2013 The Chromium Authors. All rights reserved.
  Use of this source code is governed by a BSD-style license that can be
  found in the LICENSE file.
 */
 
 body {
   -webkit-box-pack: center;
   -webkit-user-select: none;
   background-color: #0b0b0b;
@@ skipping 234 matching lines @@
 }
 
 .reload {
   background-image: url('images/reload.svg');
 }
 
 .right {
   background-image: url('images/right.svg');
 }
 
+.search{
+  background-image: url('images/search.svg');
+}
+
 .shutdown {
   background-image: url('images/shutdown.svg');
 }
 
 .up {
   background-image: url('images/up.svg');
 }
 
 .volume-down {
   background-image: url('images/volume-down.svg');
@@ skipping 10 matching lines @@
 .brightness-down,
 .brightness-up,
 .change-window,
 .down,
 .forward,
 .fullscreen,
 .left,
 .mute,
 .reload,
 .right,
+.search,
 .shutdown,
 .up,
 .volume-down,
 .volume-up {
   background-size:50%;
 }