Standardize size of WebUI controls for touch and non-touch.

chrome/browser/resources/options2/browser_options.css

 /* Copyright (c) 2012 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. */
 
 #change-home-page-section {
   margin-left: 30px;
 }
 
 #home-page-url {
   display: inline-block;
@@ skipping 396 matching lines @@
 }
 
 #auto-open-file-types-label {
   padding: 0.45em 0
 }
 
 .sliding {
   -webkit-transition: height 200ms;
   overflow-y: hidden;
 }
+
+#keyboard-overlay .option-value > select {
+  width: 100%;
+}
+
+#keyboard-overlay table {
+  /* Same as .settings-row {margin}. */
+  -webkit-border-vertical-spacing: 0.65em;
+}