CSS clean-up.

remoting/webapp/connection_history.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.
  */
 
 #connection-history-dialog {
   margin-top: -80px;
   height: 580px;
   width: 880px;
 }
 
 #connection-history-options {
   margin-top: 30px;
   display: -webkit-box;
 }
 
 #connection-history-scroller {
   margin-top: 30px;
   height: 370px;
   width: 100%;
   overflow: auto;
 }
 
 #connection-history-table {
   width: 100%;
   line-height: 2.1;
   border-bottom: 1px solid #ebebeb;
+  border-collapse: separate;
+  border-spacing: 0;
 }
 
 #connection-history-table td:last-child {
   text-align: right;
 }
 
 #connection-history-table thead td {
   font-weight: bold;
 }
 
@@ skipping 41 matching lines @@
   background-image: url('disclosure_arrow_down.png');
 }
 
 .zippy {
   width: 30px;
   height: 11px;
   background-image: url('disclosure_arrow_right.png');
   background-repeat: no-repeat;
   background-position: 10px 50%;
 }