Comment 24 for bug 1572270

Reviewed: https://review.opencontrail.org/20226
Committed: http://github.org/Juniper/contrail-controller/commit/eb7e5a11b3334d1d58ca8b0cd8103a31d6b49bea
Submitter: Zuul
Branch: master

commit eb7e5a11b3334d1d58ca8b0cd8103a31d6b49bea
Author: Praveen K V <email address hidden>
Date: Fri Apr 29 15:58:11 2016 +0530

Unify flow-update handling

The current code handles flow-update resulting from add/change for
DBEntries (interface, acl, vn, nh) as different cases. However, there is
only a minor difference between handling based on different DBEntries.

This commit unifies the code to handle DBEntry add/change into two
cases,
- Flows need re-valuation. This is case where we only do
policy-lookup and identify new actions
- Flows needing re-computation. This is case where there is route
change and flow need complete re-valuation due to add/delete of
routes

Additionally, two flags are added in flow to ensure state-compression.

Conflicts:
 src/vnsw/agent/pkt/flow_entry.cc

Change-Id: Ifeb696d2ab651f656fbafd45e5e66a52adb65ade
Partial-Bug: #1568126
Partial-Bug: #1572270
Partial-Bug: #1572471