Migrate proxy-settings.html to options2.

chrome/browser/resources/chromeos/proxy_settings.css

Index: chrome/browser/resources/chromeos/proxy_settings.css
diff --git a/chrome/browser/resources/chromeos/proxy_settings.css b/chrome/browser/resources/chromeos/proxy_settings.css
index 8537de5b664b355fff26c2cb612e6a074a538391..69f48c9d9613a490525ca09019d9dab9b5529f6e 100644
--- a/chrome/browser/resources/chromeos/proxy_settings.css
+++ b/chrome/browser/resources/chromeos/proxy_settings.css
@@ -1,3 +1,7 @@
+/* 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. */
+
 /* These additional styles constrain the size of the proxy page to the height of
    the dialog containing them. */
 html {
@@ -19,3 +23,7 @@ body {
   /* We have a title on the window, so the title in domui should be hidden. */
   display: none;
 }
+
+#internet-details-content-area > .subpages-tab-contents {
+  height: 100% !important;
+}