fix 45184 crash involving rdf literals r=alecf

mailnews/base/src/nsMsgMessageDataSource.cpp

@@ -970,10 +970,10 @@ nsresult nsMsgMessageDataSource::OnChangeStatusString(nsIRDFResource *resource,
   NS_ENSURE_SUCCESS(rv, rv);
 
 	rv = createStatusNodeFromFlag(newFlag, getter_AddRefs(newNode), PR_TRUE);
-  NS_ENSURE_TRUE(rv, rv);
+  NS_ENSURE_SUCCESS(rv, rv);
 
 	rv = NotifyPropertyChanged(resource, kNC_StatusString, newNode);
-  NS_ENSURE_TRUE(rv, rv);
+  NS_ENSURE_SUCCESS(rv, rv);
 	
 	return rv;
 }
@@ -1399,6 +1399,8 @@ nsMsgMessageDataSource::createStatusNodeFromFlag(PRUint32 flags, /*nsAutoString
 		*node = (needDisplayString) ? kNewLiteralDisplayString : kNewLiteral;
 	else if(flags & MSG_FLAG_READ)
 		*node = (needDisplayString) ? kReadLiteralDisplayString : kReadLiteral;
+
+  NS_IF_ADDREF(*node);
 	return rv;
 }
 

mailnews/base/util/nsMsgDBFolder.cpp

@@ -345,6 +345,11 @@ NS_IMETHODIMP nsMsgDBFolder::GetFirstNewMessage(nsIMessage **firstNewMessage)
 	if(NS_FAILED(rv))
 		return rv;
 
+  if (!hdr)
+  {
+    *firstNewMessage = nsnull;
+    return NS_ERROR_FAILURE;
+  }
 	rv = CreateMessageFromMsgDBHdr(hdr, firstNewMessage);
 	if(NS_FAILED(rv))
 		return rv;
@@ -432,6 +437,11 @@ nsresult nsMsgDBFolder::ReadDBFolderInfo(PRBool force)
               if (!mInitializedFromCache)
               {
                 folderInfo->GetFlags((PRInt32 *)&mFlags);
+#ifdef DEBUG_bienvenu
+                nsXPIDLString name;
+                GetName(getter_Copies(name));
+                NS_ASSERTION(nsCRT::strcmp(name, "Trash") || (mFlags & MSG_FOLDER_FLAG_TRASH), "lost trash flag");
+#endif
                 mInitializedFromCache = PR_TRUE;
               }