diff -r 000000000000 -r 6474c204b198 editor/libeditor/base/DeleteNodeTxn.cpp
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/editor/libeditor/base/DeleteNodeTxn.cpp	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,115 @@
+/* -*- 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 "DeleteNodeTxn.h"
+#include "nsDebug.h"
+#include "nsEditor.h"
+#include "nsError.h"
+#include "nsSelectionState.h" // nsRangeUpdater
+#include "nsAString.h"
+
+using namespace mozilla;
+
+DeleteNodeTxn::DeleteNodeTxn()
+  : EditTxn(), mNode(), mParent(), mRefNode(), mRangeUpdater(nullptr)
+{
+}
+
+NS_IMPL_CYCLE_COLLECTION_INHERITED(DeleteNodeTxn, EditTxn,
+                                   mNode,
+                                   mParent,
+                                   mRefNode)
+
+NS_IMPL_ADDREF_INHERITED(DeleteNodeTxn, EditTxn)
+NS_IMPL_RELEASE_INHERITED(DeleteNodeTxn, EditTxn)
+NS_INTERFACE_MAP_BEGIN_CYCLE_COLLECTION(DeleteNodeTxn)
+NS_INTERFACE_MAP_END_INHERITING(EditTxn)
+
+nsresult
+DeleteNodeTxn::Init(nsEditor* aEditor, nsINode* aNode,
+                    nsRangeUpdater* aRangeUpdater)
+{
+  NS_ENSURE_TRUE(aEditor && aNode, NS_ERROR_NULL_POINTER);
+  mEditor = aEditor;
+  mNode = aNode;
+  mParent = aNode->GetParentNode();
+
+  // do nothing if the node has a parent and it's read-only
+  NS_ENSURE_TRUE(!mParent || mEditor->IsModifiableNode(mParent),
+                 NS_ERROR_FAILURE);
+
+  mRangeUpdater = aRangeUpdater;
+  return NS_OK;
+}
+
+
+NS_IMETHODIMP
+DeleteNodeTxn::DoTransaction()
+{
+  NS_ENSURE_TRUE(mNode, NS_ERROR_NOT_INITIALIZED);
+
+  if (!mParent) {
+    // this is a no-op, there's no parent to delete mNode from
+    return NS_OK;
+  }
+
+  // remember which child mNode was (by remembering which child was next);
+  // mRefNode can be null
+  mRefNode = mNode->GetNextSibling();
+
+  // give range updater a chance.  SelAdjDeleteNode() needs to be called
+  // *before* we do the action, unlike some of the other nsRangeStore update
+  // methods.
+  if (mRangeUpdater) {
+    mRangeUpdater->SelAdjDeleteNode(mNode->AsDOMNode());
+  }
+
+  ErrorResult error;
+  mParent->RemoveChild(*mNode, error);
+  return error.ErrorCode();
+}
+
+NS_IMETHODIMP
+DeleteNodeTxn::UndoTransaction()
+{
+  if (!mParent) {
+    // this is a legal state, the txn is a no-op
+    return NS_OK;
+  }
+  if (!mNode) {
+    return NS_ERROR_NULL_POINTER;
+  }
+
+  ErrorResult error;
+  mParent->InsertBefore(*mNode, mRefNode, error);
+  return error.ErrorCode();
+}
+
+NS_IMETHODIMP
+DeleteNodeTxn::RedoTransaction()
+{
+  if (!mParent) {
+    // this is a legal state, the txn is a no-op
+    return NS_OK;
+  }
+  if (!mNode) {
+    return NS_ERROR_NULL_POINTER;
+  }
+
+  if (mRangeUpdater) {
+    mRangeUpdater->SelAdjDeleteNode(mNode->AsDOMNode());
+  }
+
+  ErrorResult error;
+  mParent->RemoveChild(*mNode, error);
+  return error.ErrorCode();
+}
+
+NS_IMETHODIMP
+DeleteNodeTxn::GetTxnDescription(nsAString& aString)
+{
+  aString.AssignLiteral("DeleteNodeTxn");
+  return NS_OK;
+}