diff -r 000000000000 -r 6474c204b198 browser/components/preferences/in-content/tests/browser_proxy_backup.js
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/browser/components/preferences/in-content/tests/browser_proxy_backup.js	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,88 @@
+/* vim: set shiftwidth=2 tabstop=2 autoindent cindent expandtab: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+Components.utils.import("resource://gre/modules/Services.jsm");
+
+function test() {
+  waitForExplicitFinish();
+
+  // network.proxy.type needs to be backed up and restored because mochitest
+  // changes this setting from the default
+  let oldNetworkProxyType = Services.prefs.getIntPref("network.proxy.type");
+  registerCleanupFunction(function() {
+    Services.prefs.setIntPref("network.proxy.type", oldNetworkProxyType);
+    Services.prefs.clearUserPref("browser.preferences.instantApply");
+    Services.prefs.clearUserPref("network.proxy.share_proxy_settings");
+    for (let proxyType of ["http", "ssl", "ftp", "socks"]) {
+      Services.prefs.clearUserPref("network.proxy." + proxyType);
+      Services.prefs.clearUserPref("network.proxy." + proxyType + "_port");
+      if (proxyType == "http") {
+        continue;
+      }
+      Services.prefs.clearUserPref("network.proxy.backup." + proxyType);
+      Services.prefs.clearUserPref("network.proxy.backup." + proxyType + "_port");
+    }
+  });
+
+  let connectionURL = "chrome://browser/content/preferences/connection.xul";
+  let windowWatcher = Services.ww;
+
+  // instantApply must be true, otherwise connection dialog won't save
+  // when opened from in-content prefs
+  Services.prefs.setBoolPref("browser.preferences.instantApply", true);
+
+  // Set a shared proxy and a SOCKS backup
+  Services.prefs.setIntPref("network.proxy.type", 1);
+  Services.prefs.setBoolPref("network.proxy.share_proxy_settings", true);
+  Services.prefs.setCharPref("network.proxy.http", "example.com");
+  Services.prefs.setIntPref("network.proxy.http_port", 1200);
+  Services.prefs.setCharPref("network.proxy.socks", "example.com");
+  Services.prefs.setIntPref("network.proxy.socks_port", 1200);
+  Services.prefs.setCharPref("network.proxy.backup.socks", "127.0.0.1");
+  Services.prefs.setIntPref("network.proxy.backup.socks_port", 9050);
+
+  // this observer is registered after the pref tab loads
+  let observer = {
+    observe: function(aSubject, aTopic, aData) {
+      if (aTopic == "domwindowopened") {
+        // when connection window loads, run tests and acceptDialog()
+        let win = aSubject.QueryInterface(Components.interfaces.nsIDOMWindow);
+        win.addEventListener("load", function winLoadListener() {
+          win.removeEventListener("load", winLoadListener, false);
+          if (win.location.href == connectionURL) {
+            ok(true, "connection window opened");
+            win.document.documentElement.acceptDialog();
+          }
+        }, false);
+      } else if (aTopic == "domwindowclosed") {
+        // finish up when connection window closes
+        let win = aSubject.QueryInterface(Components.interfaces.nsIDOMWindow);
+        if (win.location.href == connectionURL) {
+          windowWatcher.unregisterNotification(observer);
+          ok(true, "connection window closed");
+
+          // The SOCKS backup should not be replaced by the shared value
+          is(Services.prefs.getCharPref("network.proxy.backup.socks"), "127.0.0.1", "Shared proxy backup shouldn't be replaced");
+          is(Services.prefs.getIntPref("network.proxy.backup.socks_port"), 9050, "Shared proxy port backup shouldn't be replaced");
+
+          gBrowser.removeCurrentTab();
+          finish();
+        }
+      }
+    }
+  };
+
+  /*
+  The connection dialog alone won't save onaccept since it uses type="child",
+  so it has to be opened as a sub dialog of the main pref tab.
+  Open the main tab here.
+  */
+  open_preferences(function tabOpened(aContentWindow) {
+    is(gBrowser.currentURI.spec, "about:preferences", "about:preferences loaded");
+    windowWatcher.registerNotification(observer);
+    gBrowser.contentWindow.gAdvancedPane.showConnections();
+  });
+}
+