diff -r 000000000000 -r 6474c204b198 widget/xpwidgets/GfxInfoCollector.cpp
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/widget/xpwidgets/GfxInfoCollector.cpp	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,54 @@
+/* vim: se cin sw=2 ts=2 et : */
+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*-
+ *
+ * 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 "GfxInfoCollector.h"
+#include "jsapi.h"
+#include "nsString.h"
+
+using namespace mozilla;
+using namespace widget;
+
+void
+InfoObject::DefineProperty(const char *name, int value)
+{
+  if (!mOk)
+    return;
+
+  mOk = JS_DefineProperty(mCx, mObj, name, value, JSPROP_ENUMERATE);
+}
+
+void
+InfoObject::DefineProperty(const char *name, nsAString &value)
+{
+  if (!mOk)
+    return;
+
+  const nsString &flat = PromiseFlatString(value);
+  JS::Rooted<JSString*> string(mCx, JS_NewUCStringCopyN(mCx, static_cast<const jschar*>(flat.get()),
+                                                        flat.Length()));
+  if (!string)
+    mOk = false;
+
+  if (!mOk)
+    return;
+
+  mOk = JS_DefineProperty(mCx, mObj, name, string, JSPROP_ENUMERATE);
+}
+
+void
+InfoObject::DefineProperty(const char *name, const char *value)
+{
+  nsAutoString string = NS_ConvertASCIItoUTF16(value);
+  DefineProperty(name, string);
+}
+
+InfoObject::InfoObject(JSContext *aCx) : mCx(aCx), mObj(aCx), mOk(true)
+{
+  mObj = JS_NewObject(mCx, nullptr, JS::NullPtr(), JS::NullPtr());
+  if (!mObj)
+    mOk = false;
+}