Tests: Make "_DEBUG_REFRAME" report frames that became unusable.
Tests: Make "_DEBUG_REFRAME" report frames that became unusable.

* This feature got lost some time ago, but is handy to tell that
  frame caching is working as expected.

wfxiang08/Nuitka,kayhayen/Nuitka,tempbottle/Nuitka,wfxiang08/Nuitka,kayhayen/Nuitka,wfxiang08/Nuitka,kayhayen/Nuitka,kayhayen/Nuitka,tempbottle/Nuitka,tempbottle/Nuitka,wfxiang08/Nuitka,tempbottle/Nuitka