Adds IVS unit tests for new VIF firewall logic

Adds new unit tests for the IVS VIF driver to
cover the various possible plugging behaviors
added by the vif_details based logic introduced
in change I3bbcfc67036ab7389c82720add0bc0fc627bfee0.

Closes-Bug: #1301087
Change-Id: I7f0a1460b948a852c2d61d24217bbf27a4d85859
Merge "Adds IVS unit tests for new VIF firewall logic"