diff -r 000000000000 -r 6474c204b198 extensions/cookie/test/unit_ipc/test_child.js
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/extensions/cookie/test/unit_ipc/test_child.js	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,58 @@
+const Ci = Components.interfaces;
+const Cc = Components.classes;
+const Cr = Components.results;
+
+var gIoService = Components.classes["@mozilla.org/network/io-service;1"]
+                           .getService(Components.interfaces.nsIIOService);
+
+function isParentProcess() {
+    let appInfo = Cc["@mozilla.org/xre/app-info;1"];
+    return (!appInfo || appInfo.getService(Ci.nsIXULRuntime).processType == Ci.nsIXULRuntime.PROCESS_TYPE_DEFAULT);
+}
+
+function getPrincipalForURI(aURI) {
+  var uri =  gIoService.newURI(aURI, null, null);
+  return Components.classes["@mozilla.org/scriptsecuritymanager;1"]
+                   .getService(Ci.nsIScriptSecurityManager)
+                   .getNoAppCodebasePrincipal(uri);
+}
+
+function run_test() {
+  if (!isParentProcess()) {
+    const Ci = Components.interfaces;
+    const Cc = Components.classes;
+
+    var mM = Cc["@mozilla.org/childprocessmessagemanager;1"].
+                         getService(Ci.nsISyncMessageSender);
+
+    var messageListener = {
+      receiveMessage: function(aMessage) {
+        switch(aMessage.name) {
+          case "TESTING:Stage2A":
+            // Permissions created after the child is present
+            do_check_eq(pm.testPermissionFromPrincipal(getPrincipalForURI("http://mozilla.org"), "cookie1"), pm.ALLOW_ACTION);
+            do_check_eq(pm.testPermissionFromPrincipal(getPrincipalForURI("http://mozilla.com"), "cookie2"), pm.DENY_ACTION);
+            do_check_eq(pm.testPermissionFromPrincipal(getPrincipalForURI("http://mozilla.net"), "cookie3"), pm.ALLOW_ACTION);
+            do_check_eq(pm.testPermissionFromPrincipal(getPrincipalForURI("http://firefox.org"), "cookie1"), pm.ALLOW_ACTION);
+            do_check_eq(pm.testPermissionFromPrincipal(getPrincipalForURI("http://firefox.com"), "cookie2"), pm.DENY_ACTION);
+            do_check_eq(pm.testPermissionFromPrincipal(getPrincipalForURI("http://firefox.net"), "cookie3"), pm.ALLOW_ACTION);
+
+            mM.sendAsyncMessage("TESTING:Stage3");
+            break;
+
+        }
+        return true;
+      },
+    };
+
+    mM.addMessageListener("TESTING:Stage2A", messageListener);
+
+    var pm = Cc["@mozilla.org/permissionmanager;1"].getService(Ci.nsIPermissionManager);
+    do_check_eq(pm.testPermissionFromPrincipal(getPrincipalForURI("http://mozilla.org"), "cookie1"), pm.ALLOW_ACTION);
+    do_check_eq(pm.testPermissionFromPrincipal(getPrincipalForURI("http://mozilla.com"), "cookie2"), pm.DENY_ACTION);
+    do_check_eq(pm.testPermissionFromPrincipal(getPrincipalForURI("http://mozilla.net"), "cookie3"), pm.ALLOW_ACTION);
+
+    mM.sendAsyncMessage("TESTING:Stage2");
+  }
+}
+