diff -r 000000000000 -r 6474c204b198 dom/workers/ChromeWorkerScope.cpp
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/dom/workers/ChromeWorkerScope.cpp	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,73 @@
+/* -*- Mode: c++; c-basic-offset: 2; indent-tabs-mode: nil; tab-width: 40 -*- */
+/* 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/. */
+
+#include "ChromeWorkerScope.h"
+
+#include "jsapi.h"
+
+#include "nsXPCOM.h"
+#include "nsNativeCharsetUtils.h"
+#include "nsString.h"
+
+#include "WorkerPrivate.h"
+
+using namespace mozilla::dom;
+USING_WORKERS_NAMESPACE
+
+namespace {
+
+#ifdef BUILD_CTYPES
+
+char*
+UnicodeToNative(JSContext* aCx, const jschar* aSource, size_t aSourceLen)
+{
+  nsDependentString unicode(aSource, aSourceLen);
+
+  nsAutoCString native;
+  if (NS_FAILED(NS_CopyUnicodeToNative(unicode, native))) {
+    JS_ReportError(aCx, "Could not convert string to native charset!");
+    return nullptr;
+  }
+
+  char* result = static_cast<char*>(JS_malloc(aCx, native.Length() + 1));
+  if (!result) {
+    return nullptr;
+  }
+
+  memcpy(result, native.get(), native.Length());
+  result[native.Length()] = 0;
+  return result;
+}
+
+#endif // BUILD_CTYPES
+
+} // anonymous namespace
+
+BEGIN_WORKERS_NAMESPACE
+
+bool
+DefineChromeWorkerFunctions(JSContext* aCx, JS::Handle<JSObject*> aGlobal)
+{
+  // Currently ctypes is the only special property given to ChromeWorkers.
+#ifdef BUILD_CTYPES
+  {
+    JS::Rooted<JS::Value> ctypes(aCx);
+    if (!JS_InitCTypesClass(aCx, aGlobal) ||
+        !JS_GetProperty(aCx, aGlobal, "ctypes", &ctypes)) {
+      return false;
+    }
+
+    static JSCTypesCallbacks callbacks = {
+      UnicodeToNative
+    };
+
+    JS_SetCTypesCallbacks(JSVAL_TO_OBJECT(ctypes), &callbacks);
+  }
+#endif // BUILD_CTYPES
+
+  return true;
+}
+
+END_WORKERS_NAMESPACE