diff -r 000000000000 -r 6474c204b198 toolkit/content/tests/widgets/videocontrols_direction_test.js
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/toolkit/content/tests/widgets/videocontrols_direction_test.js	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,92 @@
+var RemoteCanvas = function(url, id) {
+  this.url = url;
+  this.id = id;
+  this.snapshot = null;
+};
+
+RemoteCanvas.CANVAS_WIDTH = 200;
+RemoteCanvas.CANVAS_HEIGHT = 200;
+
+RemoteCanvas.prototype.compare = function(otherCanvas, expected) {
+  return compareSnapshots(this.snapshot, otherCanvas.snapshot, expected)[0];
+}
+
+RemoteCanvas.prototype.load = function(callback) {
+  var iframe = document.createElement("iframe");
+  iframe.id = this.id + "-iframe";
+  iframe.width = RemoteCanvas.CANVAS_WIDTH + "px";
+  iframe.height = RemoteCanvas.CANVAS_HEIGHT + "px";
+  iframe.src = this.url;
+  var me = this;
+  iframe.addEventListener("load", function() {
+    var m = iframe.contentDocument.getElementById("av");
+    m.addEventListener("progress", function(aEvent) {
+      var v = aEvent.target;
+      var b = v.buffered;
+      if (b.length == 1 && b.end(0) == v.duration) {
+        m.removeEventListener("progress", arguments.callee, false);
+        setTimeout(function() {
+          me.remotePageLoaded(callback);
+        }, 0);
+      }
+    }, false);
+    m.src = m.getAttribute("source");
+  }, false);
+  window.document.body.appendChild(iframe);
+};
+
+RemoteCanvas.prototype.remotePageLoaded = function(callback) {
+  var ldrFrame = document.getElementById(this.id + "-iframe");
+  this.snapshot = snapshotWindow(ldrFrame.contentWindow);
+  this.snapshot.id = this.id + "-canvas";
+  window.document.body.appendChild(this.snapshot);
+  callback(this);
+};
+
+RemoteCanvas.prototype.cleanup = function() {
+  var iframe = document.getElementById(this.id + "-iframe");
+  iframe.parentNode.removeChild(iframe);
+  var canvas = document.getElementById(this.id + "-canvas");
+  canvas.parentNode.removeChild(canvas);
+};
+
+function runTest(index) {
+  var canvases = [];
+  function testCallback(canvas) {
+    canvases.push(canvas);
+
+    if (canvases.length == 2) { // when both canvases are loaded
+      var expectedEqual = currentTest.op == "==";
+      var result = canvases[0].compare(canvases[1], expectedEqual);
+      ok(result, "Rendering of reftest " + currentTest.test + " should " +
+        (expectedEqual ? "not " : "") + "be different to the reference");
+
+      if (result) {
+        canvases[0].cleanup();
+        canvases[1].cleanup();
+      }
+      else {
+        ok(true, "Snapshot of canvas 1: " + canvases[0].snapshot.toDataURL());
+        ok(true, "Snapshot of canvas 2: " + canvases[1].snapshot.toDataURL());
+      }
+
+      if (index < tests.length - 1)
+        runTest(index + 1);
+      else
+        SimpleTest.finish();
+    }
+  }
+
+  var currentTest = tests[index];
+  var testCanvas = new RemoteCanvas(currentTest.test, "test-" + index);
+  testCanvas.load(testCallback);
+
+  var refCanvas = new RemoteCanvas(currentTest.ref, "ref-" + index);
+  refCanvas.load(testCallback);
+}
+
+SimpleTest.waitForExplicitFinish();
+
+window.addEventListener("load", function() {
+  SpecialPowers.pushPrefEnv({"set": [["media.cache_size", 40000]]}, function(){ runTest(0); });
+}, true);