Add Media Router route-details.

chrome/browser/resources/media_router/elements/route_details/route_details.css

+/* Copyright 2015 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. */
+
+#back-to-devices {
+  -webkit-padding-start: 10px;
+  color: rgb(20, 86, 218);
+  font-weight: bold;
+  line-height: 2em;
+}
+
+#back-to-devices:hover {
+  cursor: pointer;
+  text-decoration: underline;
+}
+
+button {
+  background: linear-gradient(to top, rgb(254, 254, 254), rgb(222, 222, 222));
+}
+
+.device-name {
+  font-weight: bold;
+}
+
+hr {
+  margin: 0;
+}
+
+.route {
+  -webkit-padding-start: 10px;
+  line-height: 1.125em;
+}
+
+.route-status {
+  color: rgb(125, 125, 125);
+  margin: 8px 0;
+}
+
+.route-title {
+  font-weight: bold;
+  margin: 8px 0;
+  overflow: hidden;
+}