First try at a user management screen for the desktop

chrome/browser/resources/user_chooser/header_bar.css

Index: chrome/browser/resources/user_chooser/header_bar.css
diff --git a/chrome/browser/resources/user_chooser/header_bar.css b/chrome/browser/resources/user_chooser/header_bar.css
new file mode 100644
index 0000000000000000000000000000000000000000..749f352b2423c6ff774feecab22adc0042090856
--- /dev/null
+++ b/chrome/browser/resources/user_chooser/header_bar.css
@@ -0,0 +1,38 @@
+/* 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.
+ */
+
+/* Overrides of styles in chrome/browser/resources/chromeos/login/header_bar.js
+* that are needed by the desktop user chooser screen
+*/
+#login-header-bar {
+  background-image: none;
+}
+
+#login-header-bar button,
+#login-header-bar button:active,
+#login-header-bar button:focus,
+#login-header-bar button:hover {
+  -webkit-box-shadow: none;
+  background: transparent none;
+  border: none;
+  border-radius: 3px;
+  cursor: pointer;
+  height: 34px;
+  margin: 0;
+  min-width: 0;
+  opacity: 0.6;
+  padding: 5px 8px;
+  vertical-align: middle;
+}
+
+#login-header-bar #add-user-button {
+  background-color: #505050;
+  background-image: url('chrome://theme/IDR_ICON_ADD_USER_WHITE');
+}
+
+#login-header-bar #guest-user-button {
+  background-color: #505050;
+  background-image: url('chrome://theme/IDR_ICON_GUEST_WHITE');
+}