Issue 4125 - [emscripten] Convert filter classes to C++

test.js

+#!/usr/bin/env node --harmony
+"use strict";
+
+require("node-babel")({
+  extensions: [".js"],
+  ignore: /\bcompiled\b/,
+  blacklist: ["useStrict"]
+});
+
+// HACK: override Node's module resolution to match the way bootstrap.js
+// resolves modules right now.
+let nodeModule = require("module");
+let origResolve = nodeModule._resolveFilename;
+nodeModule._resolveFilename = function()
+{
+  let params = Array.slice(arguments);
+  if (params[0] == "compiled")
+    params[0] = "./compiled";
+  else if (params[0] == "filterClasses")
+    params[0] = "./filterClassesNew";
+  else if (params[0] == "../lib/filterClasses")
+    params[0] = "../lib/filterClassesNew";
+  else if (params[0] == "filterNotifier")
+    params[0] = "./filterNotifier";
+  return origResolve.apply(this, params);
+};
+
+require("nodeunit").reporters.default.run(["test"]);