Fix crash for ftp:// and file:// urls that have no useful extension and

binary data.  r=bbaetz, sr=mscott, a=asa


git-svn-id: svn://10.0.0.236/trunk@107681 18797224-902f-48f8-a5cc-f745e15eee43

mozilla/uriloader/exthandler/nsExternalHelperAppService.cpp

@@ -1555,6 +1555,7 @@ nsresult nsExternalHelperAppService::GetMIMEInfoForMimeTypeFromExtras(const char
           mimeInfo->SetMacCreator(extraMimeEntries[index].mMacCreator);
 
           *aMIMEInfo = mimeInfo;
+          NS_ADDREF(*aMIMEInfo);
       }
   }