I did change it back to 14, but the issue is happening nonetheless. So I guess it does not matter what targeted sdk is, the issue is there.
Further info: when I click on the toolbar menu (three dots) and the overflow menu is shown, then every time i press the hardware menu key it close it. Every time no exception. This is perfect! The opposite is not quite the same. When i press hardware menu key, some times it does nothing, sometimes it show the overflow menu but very quickly it hide it back, and only a few times it show the overflow menu without problem. Is just like triggering show/hide almost instantly(but I only press it once), with a few exceptions("normal cases").
Maybe this code is not foolproof. Is there a code (hack) to trick the system into thinking there is no hardware menu key? Will this be a better aproach? I am lost...(well...not quite...but...)