[WebUI] Fix all CSS nits in chrome/browser/resources/chromeos.

chrome/browser/resources/chromeos/wrench_menu.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.
+ */
+
 .fullscreen {
+  -webkit-margin-start: 4px;
   background-image: url('../../../app/theme/fullscreen_menu_button.png');
   background-position: center center;
   background-repeat: no-repeat;
   border: solid 1px rgba(0, 0, 0, 0.3);
   border-radius: 3px;
+  height: 23px;
   width: 23px;
-  height: 23px;
-  -webkit-margin-start: 4px;
 }
 
 .edit-button {
+  min-width: 35px;
   padding: 2px;
   text-align: center;
-  min-width: 35px;
 }
 
 .left-button {
   border: solid 1px rgba(0, 0, 0, 0.3);
+  border-bottom-left-radius: 3px;
   border-top-left-radius: 3px;
-  border-bottom-left-radius: 3px;
 }
 
 .right-button {
   border: solid 1px rgba(0, 0, 0, 0.3);
+  border-bottom-right-radius: 3px;
   border-top-right-radius: 3px;
-  border-bottom-right-radius: 3px;
 }
 
 .center-button {
+  border-bottom: solid 1px rgba(0, 0, 0, 0.3);
   border-top: solid 1px rgba(0, 0, 0, 0.3);
-  border-bottom: solid 1px rgba(0, 0, 0, 0.3);
 }
 
 .zoom-button {
   text-align: center;
   width: 15px;
 }
 
 .zoom-percent {
   min-width: 40px;
   text-align: center;
 }