Fix port notification update in L3 plugin
Fix port notification update in L3 plugin

Change-Id: Id2b3cd6baee81dff0cb2904c4fb5595bfde7fc51
Closes-bug: 1508750

jiahaoliang/group-based-policy,jiahaoliang/group-based-policy,noironetworks/group-based-policy,noironetworks/group-based-policy,stackforge/group-based-policy,stackforge/group-based-policy