Issue #2976334 by tedbow, Wim Leers, johndevman, tim.plunkett, amateescu,...

Issue #2976334 by tedbow, Wim Leers, johndevman, tim.plunkett, amateescu, phenaproxima, larowlan, Berdir, EclipseGc, samuel.mortenson, johnzzon: Allow Custom blocks to be set as non-reusable adding access restriction based on where it was used

(cherry picked from commit 9d6dcefd)