Fix a possibility to overcome BLOCK permission

This patch closes the possibility to overwrite BLOCK
permission from parent project by simply re-adding exactly
the same BLOCK entry followed by ALLOW entry in the child project.

The two new unit tests in RefControlTest show the problem.

Change-Id: I0bf0f0cd549185d72f8753d04f02d87d8709a3b2
Signed-off-by: Eryk Szymanski <eryksz@gmail.com>
2 files changed