diff -r 000000000000 -r 6474c204b198 netwerk/test/unit/test_bug510359.js
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/netwerk/test/unit/test_bug510359.js	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,77 @@
+Cu.import("resource://testing-common/httpd.js");
+
+var httpserver = new HttpServer();
+var index = 0;
+var tests = [
+    { url : "/bug510359", server : "0", expected : "0"},
+    { url : "/bug510359", server : "1", expected : "1"},
+];
+
+function setupChannel(suffix, value) {
+    var ios = Components.classes["@mozilla.org/network/io-service;1"]
+            .getService(Ci.nsIIOService);
+    var chan = ios.newChannel("http://localhost:" +
+                              httpserver.identity.primaryPort +
+                              suffix, "", null);
+    var httpChan = chan.QueryInterface(Components.interfaces.nsIHttpChannel);
+    httpChan.requestMethod = "GET";
+    httpChan.setRequestHeader("x-request", value, false);
+    httpChan.setRequestHeader("Cookie", "c="+value, false);
+    return httpChan;
+}
+
+function triggerNextTest() {
+    var channel = setupChannel(tests[index].url, tests[index].server);
+    channel.asyncOpen(new ChannelListener(checkValueAndTrigger, null), null);
+}
+
+function checkValueAndTrigger(request, data, ctx) {
+    do_check_eq(tests[index].expected, data);
+
+    if (index < tests.length - 1) {
+        index++;
+        triggerNextTest();
+    } else {
+        httpserver.stop(do_test_finished);
+    }
+}
+
+function run_test() {
+    httpserver.registerPathHandler("/bug510359", handler);
+    httpserver.start(-1);
+
+    // clear cache
+    evict_cache_entries();
+
+    triggerNextTest();
+
+    do_test_pending();
+}
+
+function handler(metadata, response) {
+    try {
+        var IMS = metadata.getHeader("If-Modified-Since");
+        response.setStatusLine(metadata.httpVersion, 500, "Failed");
+        var msg = "Client should not set If-Modified-Since header";
+        response.bodyOutputStream.write(msg, msg.length);
+    } catch(ex) {
+        response.setStatusLine(metadata.httpVersion, 200, "Ok");
+        response.setHeader("Content-Type", "text/plain", false);
+        response.setHeader("Last-Modified", getDateString(-1), false);
+        response.setHeader("Vary", "Cookie", false);
+        var body = metadata.getHeader("x-request");
+        response.bodyOutputStream.write(body, body.length);
+    }
+}
+
+function getDateString(yearDelta) {
+    var months = [ 'Jan', 'Feb', 'Mar', 'Apr', 'May', 'Jun', 'Jul', 'Aug',
+            'Sep', 'Oct', 'Nov', 'Dec' ];
+    var days = [ 'Sun', 'Mon', 'Tue', 'Wed', 'Thu', 'Fri', 'Sat' ];
+
+    var d = new Date();
+    return days[d.getUTCDay()] + ", " + d.getUTCDate() + " "
+            + months[d.getUTCMonth()] + " " + (d.getUTCFullYear() + yearDelta)
+            + " " + d.getUTCHours() + ":" + d.getUTCMinutes() + ":"
+            + d.getUTCSeconds() + " UTC";
+}