From d03b3983a0c7e6e337577c2fcb22fe6ed4e8cb86 Mon Sep 17 00:00:00 2001
From: Olli Pettay <Olli.Pettay@helsinki.fi>
Date: Thu, 23 Feb 2012 22:47:37 +0200
Subject: [PATCH] Bug 730013 - don't addref/release nsTransactionManager so
 much to prevent it to end up to the purple buffer, r=ehsan

---
 content/html/content/src/nsTextEditorState.cpp |  8 ++------
 editor/idl/nsIEditor.idl                       | 12 +++++++++++-
 editor/libeditor/base/nsEditor.cpp             | 13 +++++++++++++
 3 files changed, 26 insertions(+), 7 deletions(-)

diff --git a/content/html/content/src/nsTextEditorState.cpp b/content/html/content/src/nsTextEditorState.cpp
index 2eb62ab716f..2f79c1a78aa 100644
--- a/content/html/content/src/nsTextEditorState.cpp
+++ b/content/html/content/src/nsTextEditorState.cpp
@@ -849,15 +849,11 @@ nsTextInputListener::EditAction()
   nsCOMPtr<nsIEditor> editor;
   frame->GetEditor(getter_AddRefs(editor));
 
-  nsCOMPtr<nsITransactionManager> manager;
-  editor->GetTransactionManager(getter_AddRefs(manager));
-  NS_ENSURE_TRUE(manager, NS_ERROR_FAILURE);
-
   // Get the number of undo / redo items
   PRInt32 numUndoItems = 0;
   PRInt32 numRedoItems = 0;
-  manager->GetNumberOfUndoItems(&numUndoItems);
-  manager->GetNumberOfRedoItems(&numRedoItems);
+  editor->GetNumberOfUndoItems(&numUndoItems);
+  editor->GetNumberOfRedoItems(&numRedoItems);
   if ((numUndoItems && !mHadUndoItems) || (!numUndoItems && mHadUndoItems) ||
       (numRedoItems && !mHadRedoItems) || (!numRedoItems && mHadRedoItems)) {
     // Modify the menu if undo or redo items are different
diff --git a/editor/idl/nsIEditor.idl b/editor/idl/nsIEditor.idl
index 052592a7f74..d4a9c91c431 100644
--- a/editor/idl/nsIEditor.idl
+++ b/editor/idl/nsIEditor.idl
@@ -55,7 +55,7 @@ interface nsIEditActionListener;
 interface nsIInlineSpellChecker;
 interface nsITransferable;
 
-[scriptable, uuid(94479B76-7FD7-47D3-BB1E-5B77846339D2)]
+[scriptable, uuid(656005d2-d900-4839-81bf-6274a3c38537)]
 
 interface nsIEditor  : nsISupports
 {
@@ -205,6 +205,16 @@ interface nsIEditor  : nsISupports
     */
   void enableUndo(in boolean enable);
 
+  /**
+   * The number of items on the undo stack.
+   */
+  readonly attribute long numberOfUndoItems;
+
+  /**
+   * The number of items on the redo stack.
+   */
+  readonly attribute long numberOfRedoItems;
+
   /** undo reverses the effects of the last Do operation,
     * if Undo is enabled in the editor.
     * It is provided here so clients need no knowledge of whether
diff --git a/editor/libeditor/base/nsEditor.cpp b/editor/libeditor/base/nsEditor.cpp
index 197c9f2b000..8f06173bb64 100644
--- a/editor/libeditor/base/nsEditor.cpp
+++ b/editor/libeditor/base/nsEditor.cpp
@@ -750,6 +750,19 @@ nsEditor::EnableUndo(bool aEnable)
   return NS_OK;
 }
 
+NS_IMETHODIMP
+nsEditor::GetNumberOfUndoItems(PRInt32* aNumItems)
+{
+  *aNumItems = 0;
+  return mTxnMgr ? mTxnMgr->GetNumberOfUndoItems(aNumItems) : NS_OK;
+}
+
+NS_IMETHODIMP
+nsEditor::GetNumberOfRedoItems(PRInt32* aNumItems)
+{
+  *aNumItems = 0;
+  return mTxnMgr ? mTxnMgr->GetNumberOfRedoItems(aNumItems) : NS_OK;
+}
 
 NS_IMETHODIMP
 nsEditor::GetTransactionManager(nsITransactionManager* *aTxnManager)