[l3vpn_ecmp] Groupstats not updated if traffic initiated after deletion and readdition of extra route on VM.

Topology
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3CSS, 1 DC-GW, 6 VMs, 2 each on each CSS.

Build used
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distribution-karaf-0.6.0-20170522.002211-5360.zip

Steps to repro
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1)Do the basic vxlan configuration for one CSS.
2)Configure mpls over gre.Check it is configured properly.
3)Form bgp neigborship between Controller and DC-GW and check check bgp neighborship.
4)Configure two VMs on CSS-1, CSS-2 and CSS-3 using nova command.
5)Configure bgvpn update with one rd.Check whether it is advertised to DC-GW.
6)Configure extra route using "router update command"
neutron router-update ROUTER1 --routes type=dict list=true destination=200.0.0.0/24,nexthop=10.10.10.2
destination=200.0.0.0/24,nexthop=10.10.10.3 destination=201.0.0.0/24,nexthop=10.10.10.4
destination=201.0.0.0/24,nexthop=10.10.10.5 destination=200.0.0.0/24,nexthop=10.10.10.4
7)Check these VM entries updated in "show ip route" in vpn context.
8)Configure a static ip ( extra route) on VM-1 in DPN1.
ifconfig eth0:0 200.0.0.2 up
9)Also configure a static ip ( extra route) on VM-1 in DPN1.
ifconfig eth0:0 200.0.0.3 up
10)Check the extra routes are also advertised to SER.
11) Ping 200.0.0.3 from 200.0.0.2, it works. statsis also updated.
12)Delete and reconfigure the ip on VM1( delete and reconfigure 200.0.0.2)
13)Initiate ping, it works but this time stat is not updating.

Logs
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Logs attached.