Bug 1915397 - fix resource leaks in mime_parse_stream_complete. r=BenC

CID: 1137489
CID: 1137488

Differential Revision: https://phabricator.services.mozilla.com/D223678

--HG--
extra : rebase_source : 9240181f632d2e43e8e02f4e2d0541d0c20c9f99
extra : amend_source : 6637a0240f8f3400e65984bbfdf7d1070d8058e1

mailnews/mime/src/mimedrft.cpp

@@ -1417,7 +1417,11 @@ static void mime_parse_stream_complete(nsMIMESession* stream) {
 
           nsresult rv = NS_NewLocalFileInputStream(getter_AddRefs(inputStream),
                                                    mdd->messageBody->m_tmpFile);
-          if (NS_FAILED(rv)) return;
+          if (NS_FAILED(rv)) {
+            delete[] newAttachData;
+            PR_Free(body);
+            return;
+          }
 
           inputStream->Read(body, bodyLen, &bytesRead);