diff -r 000000000000 -r 6474c204b198 content/base/src/Comment.cpp
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/content/base/src/Comment.cpp	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,83 @@
+/* -*- 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/. */
+
+/*
+ * Implementations of DOM Core's nsIDOMComment node.
+ */
+
+#include "nsCOMPtr.h"
+#include "mozilla/dom/Comment.h"
+#include "mozilla/dom/CommentBinding.h"
+#include "mozilla/IntegerPrintfMacros.h"
+
+using namespace mozilla;
+using namespace dom;
+
+namespace mozilla {
+namespace dom {
+
+Comment::~Comment()
+{
+}
+
+NS_IMPL_ISUPPORTS_INHERITED(Comment, nsGenericDOMDataNode, nsIDOMNode,
+                            nsIDOMCharacterData, nsIDOMComment)
+
+bool
+Comment::IsNodeOfType(uint32_t aFlags) const
+{
+  return !(aFlags & ~(eCONTENT | eCOMMENT | eDATA_NODE));
+}
+
+nsGenericDOMDataNode*
+Comment::CloneDataNode(nsINodeInfo *aNodeInfo, bool aCloneText) const
+{
+  nsCOMPtr<nsINodeInfo> ni = aNodeInfo;
+  Comment *it = new Comment(ni.forget());
+  if (it && aCloneText) {
+    it->mText = mText;
+  }
+
+  return it;
+}
+
+#ifdef DEBUG
+void
+Comment::List(FILE* out, int32_t aIndent) const
+{
+  int32_t indx;
+  for (indx = aIndent; --indx >= 0; ) fputs("  ", out);
+
+  fprintf(out, "Comment@%p refcount=%" PRIuPTR "<!--", (void*)this, mRefCnt.get());
+
+  nsAutoString tmp;
+  ToCString(tmp, 0, mText.GetLength());
+  fputs(NS_LossyConvertUTF16toASCII(tmp).get(), out);
+
+  fputs("-->\n", out);
+}
+#endif
+
+/* static */ already_AddRefed<Comment>
+Comment::Constructor(const GlobalObject& aGlobal,
+                     const nsAString& aData, ErrorResult& aRv)
+{
+  nsCOMPtr<nsPIDOMWindow> window = do_QueryInterface(aGlobal.GetAsSupports());
+  if (!window || !window->GetDoc()) {
+    aRv.Throw(NS_ERROR_FAILURE);
+    return nullptr;
+  }
+
+  return window->GetDoc()->CreateComment(aData);
+}
+
+JSObject*
+Comment::WrapNode(JSContext *aCx)
+{
+  return CommentBinding::Wrap(aCx, this);
+}
+
+} // namespace dom
+} // namespace mozilla