R5.0-283: rflow index is set to -1 for all evicted flows

[alok kumar]

In regression, tcp eviction cases are failing in evicted flow verification.

on debugging it was seen that in test script we expect value of rflow other than '-1' to get the reverse flow index for a particular forward flow.

in method get_flow_entry:

                forward_flow = FlowEntry(flow_entry_item)
                if flow_entry_item['rflow'] != '-1':
                    reverse_flow_item = [x for x
                        in flow_table.items
                        if x['index']==forward_flow.r_flow_index][0]

but for evicted flows rflow is always set to -1, so we can't identify reverse flow for a forward flow and causing the test failure.

since this is old case and used to pass, not sure if this behaviour is changed or something else is causing the issue in 5.0.

however there was probably script issue too which I have fixed but still test is failing due to above mentioned reason.
Need input from vrouter team for the issue.

[alok kumar (kalok)]

Snh_KFlowReq is used from agent introspect to get the flow entry.

http://10.204.216.98:8085/Snh_KFlowReq?flow_idx=&show_evicted=1