fix for 41770 - new filters were not saving

- any kind of error during filter creation was not clearing gFilter,
  which meant the filter would not get added to the filterlist
- the filter type was uninitialized, so none of the rules would get saved

mailnews/base/search/resources/content/FilterEditor.js

@@ -161,6 +161,7 @@ function saveFilter() {
         if (!targetUri || targetUri == "") {
             var str = Bundle.GetStringFromName("mustSelectFolder");
             window.alert(str);
+            gFilter = null;
             return false;
         }
         gFilter.actionTargetFolderUri = targetUri;
@@ -170,13 +171,17 @@ function saveFilter() {
         if (!gActionPriority.selectedItem) {
             var str = Bundle.GetStringFromName("mustSelectPriority");
             window.alert(str);
+            gFilter = null;
             return false;
         }
         gFilter.actionPriority = gActionPriority.selectedItem.getAttribute("data");
     }
 
-    if (isNewFilter)
+    
+    if (isNewFilter) {
+        dump("new filter.. inserting into " + gFilterList + "\n");
         gFilterList.insertFilterAt(0, gFilter);
+    }
 
     // success!
     return true;

mailnews/base/search/src/nsMsgFilter.cpp

@@ -49,6 +49,7 @@ nsMsgRuleAction::~nsMsgRuleAction()
 
 
 nsMsgFilter::nsMsgFilter() :
+    m_type(1),
     m_filterList(nsnull)
 {
 	NS_INIT_REFCNT();
@@ -472,8 +473,8 @@ nsresult nsMsgFilter::SaveRule()
 	GetActionFilingStr(m_action.m_type, actionFilingStr);
 
 	err = filterList->WriteStrAttr(nsIMsgFilterList::attribAction, actionFilingStr);
-	if (!NS_SUCCEEDED(err))
-		return err;
+    NS_ENSURE_SUCCESS(err, err);
+
 	switch(m_action.m_type)
 	{
 	case nsMsgFilterAction::MoveToFolder: