Can't ping from VLAN interface which has LAG member

**Description**
_ping_ command doesn't work when I try to run it for IP address from VLAN interface subnet. VLAN interface has one member which is LAG interface. In turn LAG consist of two physical interfaces.



**Steps to reproduce the issue:**
1. Create LAG interface named _lag1_
```
config portchannel add lag1
```
2. Assign physical ports (#1 and #2) to the LAG interface
```
ip link set Ethernet0 down
ip link set Ethernet4 down
config portchannel member add lag1 Ethernet0
config portchannel member add lag1 Ethernet4
```
3. Remove existed IP addresses from physical ports
```
ip addr flush dev Ethernet0
ip addr flush dev Ethernet4
```
4. Create VLANs and assign LAG interface to the both of them
```
config vlan add 610
config vlan member add 610 lag1
config vlan add 611
config vlan member add 611 lag1
```
5. Assign IP addresses to the VLAN interfaces
```
config interface Vlan610 ip add 172.25.164.196/31
config interface Vlan610 ip add 2001:4878:c225:0000:0000:0003:0000:0001/96
config interface Vlan611 ip add 172.25.164.198/31
config interface Vlan610 ip add 2001:4878:c225:0000:0000:0004:0000:0001/96
```
6. Link up all interfaces
```
config interface Vlan610 startup
config interface Vlan611 startup
config interface lag1 startup
config interface Ethernet0 startup
config interface Ethernet4 startup
```
7. Save running config into startup
```
config save
```
8. Reboot SONiC
```
reboot
```
9. On the remote device repeat steps **1-8** except step **5** where you should allocate different IP addresses but corresponding to proper subnet of VLAN interfaces
```
config interface Vlan610 ip add 172.25.164.197/31
config interface Vlan610 ip add 2001:4878:c225:0000:0000:0003:0000:0002/96
config interface Vlan611 ip add 172.25.164.199/31
config interface Vlan610 ip add 2001:4878:c225:0000:0000:0004:0000:0002/96
```

**Describe the results you received:**
I running _ping_ command to get ARP reply from remote device , but without success:
```
root@sonic:~# ping 172.25.164.197
PING 172.25.164.197 (172.25.164.197) 56(84) bytes of data.
From 172.25.164.196 icmp_seq=1 Destination Host Unreachable
From 172.25.164.196 icmp_seq=2 Destination Host Unreachable
From 172.25.164.196 icmp_seq=3 Destination Host Unreachable
...
```

And I can see only ARP request when I want capture any traffic from _Vlan610_ interface on local machine:
```
root@sonic:~# tcpdump -i Vlan610 -en
tcpdump: verbose output suppressed, use -v or -vv for full protocol decode
listening on Vlan610, link-type EN10MB (Ethernet), capture size 262144 bytes
22:57:51.748889 3c:2c:99:02:9b:2f > ff:ff:ff:ff:ff:ff, ethertype ARP (0x0806), length 42: Request who-has 172.25.164.197 tell 172.25.164.196, length 28
22:57:52.771108 3c:2c:99:02:9b:2f > ff:ff:ff:ff:ff:ff, ethertype ARP (0x0806), length 42: Request who-has 172.25.164.197 tell 172.25.164.196, length 28
22:57:53.795004 3c:2c:99:02:9b:2f > ff:ff:ff:ff:ff:ff, ethertype ARP (0x0806), length 42: Request who-has 172.25.164.197 tell 172.25.164.196, length 28
...
```

ARP cache is still incomplete:
```
root@sonic:~# arp -n
Address                  HWtype  HWaddress           Flags Mask            Iface
172.25.164.197                   (incomplete)                              Vlan610
```

**Describe the results you expected:**
I expect to see any traffic on _Vlan610_ interface especially I would like to have resolved ARP table for IP from remote device. I also expect to capture ARP request/reply traffic during _tcpdump_ session when I run _ping_ command.

**Additional information:**
I can confirm that I cannot see any traffic from _Vlan610_ interface on remote device.

Route table dump: 
```
root@sonic:~# ip route
172.25.164.196/31 dev Vlan610 proto kernel scope link src 172.25.164.196 
172.25.164.198/31 dev Vlan611 proto kernel scope link src 172.25.164.198 
```

Link state of interfaces:
```
root@sonic:~# ip addr
8: lag1: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 9100 qdisc noqueue state UP group default qlen 1000
    link/ether 3c:2c:99:02:9b:2f brd ff:ff:ff:ff:ff:ff
    inet6 fe80::3e2c:99ff:fe02:9b2f/64 scope link 
       valid_lft forever preferred_lft forever
10: Vlan610@Bridge: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UP group default qlen 1000
    link/ether 3c:2c:99:02:9b:2f brd ff:ff:ff:ff:ff:ff
    inet 172.25.164.196/31 scope global Vlan610
       valid_lft forever preferred_lft forever
    inet6 2001:4878:c225::3:0:1/96 scope global 
       valid_lft forever preferred_lft forever
    inet6 fe80::3e2c:99ff:fe02:9b2f/64 scope link 
       valid_lft forever preferred_lft forever
11: Vlan611@Bridge: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UP group default qlen 1000
    link/ether 3c:2c:99:02:9b:2f brd ff:ff:ff:ff:ff:ff
    inet 172.25.164.198/31 scope global Vlan611
       valid_lft forever preferred_lft forever
    inet6 2001:4878:c225::4:0:1/96 scope global 
       valid_lft forever preferred_lft forever
    inet6 fe80::3e2c:99ff:fe02:9b2f/64 scope link 
       valid_lft forever preferred_lft forever
28: Ethernet4: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 9100 qdisc pfifo_fast master lag1 state UP group default qlen 1000
    link/ether 3c:2c:99:02:9b:2f brd ff:ff:ff:ff:ff:ff
    inet6 fe80::3e2c:99ff:fe02:9b2f/64 scope link 
       valid_lft forever preferred_lft forever
30: Ethernet0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 9100 qdisc pfifo_fast master lag1 state UP group default qlen 1000
    link/ether 3c:2c:99:02:9b:2f brd ff:ff:ff:ff:ff:ff
    inet6 fe80::3e2c:99ff:fe02:9b2f/64 scope link 
       valid_lft forever preferred_lft forever
```

Here is running configuration dump from `/etc/sonic/config_db.json`:
```
root@sonic:~# cat /etc/sonic/config_db.json 
{
    "VLAN_INTERFACE": {
        "Vlan610|172.25.164.196/31": {}, 
        "Vlan610|2001:4878:c225:0000:0000:0003:0000:0001/96": {}, 
        "Vlan610|2001:4878:c225:0000:0000:0004:0000:0001/96": {}, 
        "Vlan611|172.25.164.198/31": {}
    }, 
    "FLEX_COUNTER_TABLE": {
        "PFCWD": {
            "FLEX_COUNTER_STATUS": "enable"
        }, 
        "PORT": {
            "FLEX_COUNTER_STATUS": "enable"
        }, 
        "QUEUE": {
            "FLEX_COUNTER_STATUS": "enable"
        }
    }, 
    "BGP_NEIGHBOR": {
        "10.0.0.1": {
            "rrclient": "0", 
            "name": "ARISTA01T2", 
            "local_addr": "10.0.0.0", 
            "nhopself": "0", 
            "holdtime": "180", 
            "asn": "65200", 
            "keepalive": "60"
        }, 
        ...
    }, 
    "DEVICE_METADATA": {
        "localhost": {
            "hwsku": "Accton-AS7816-64X", 
            "hostname": "sonic", 
            "platform": "x86_64-accton_as7816_64x-r0", 
            "mac": "3c:2c:99:02:9b:2f", 
            "bgp_asn": "65100", 
            "type": "LeafRouter"
        }
    }, 
    "VLAN": {
        "Vlan610": {
            "members": [
                "lag1"
            ], 
            "vlanid": "610"
        }, 
        "Vlan611": {
            "members": [
                "lag1"
            ], 
            "vlanid": "611"
        }
    }, 
    "PORTCHANNEL": {
        "lag1": {
            "admin_status": "up", 
            "mtu": "9100"
        }
    }, 
    "PORT": {
        "Ethernet0": {
            "alias": "hundredGigE1", 
            "admin_status": "up", 
            "lanes": "73,74,75,76", 
            "mtu": "9100"
        }, 
        "Ethernet4": {
            "alias": "hundredGigE2", 
            "admin_status": "up", 
            "lanes": "65,66,67,68", 
            "mtu": "9100"
        }, 
        "Ethernet8": {
            "alias": "hundredGigE3", 
            "admin_status": "up", 
            "lanes": "81,82,83,84", 
            "mtu": "9100"
        }, 
        ...
    }, 
    "PORTCHANNEL_MEMBER": {
        "lag1|Ethernet0": {}, 
        "lag1|Ethernet4": {}
    }, 
    "INTERFACE": {
        "Ethernet8|10.0.0.4/31": {}, 
        "Ethernet12|10.0.0.6/31": {}, 
        ...
    }, 
    "VLAN_MEMBER": {
        "Vlan610|lag1": {
            "tagging_mode": "tagged"
        }, 
        "Vlan611|lag1": {
            "tagging_mode": "tagged"
        }
    }, 
    "LOOPBACK_INTERFACE": {
        "Loopback0|10.1.0.1/32": {}
    }
}
```

Output of `show version`:
```
ONiC Software Version: SONiC.HEAD.781-465ebba
Distribution: Debian 9.6
Kernel: 4.9.0-7-amd64
Build commit: 465ebba
Build date: Wed Nov 21 13:45:33 UTC 2018
Built by: johnar@jenkins-worker-4

Docker images:
REPOSITORY                 TAG                 IMAGE ID            SIZE
docker-syncd-brcm          HEAD.781-465ebba    3dce8ec8a958        336.2 MB
docker-syncd-brcm          latest              3dce8ec8a958        336.2 MB
docker-orchagent-brcm      HEAD.781-465ebba    f177bffee105        282.6 MB
docker-orchagent-brcm      latest              f177bffee105        282.6 MB
docker-lldp-sv2            HEAD.781-465ebba    1825d980eafc        271 MB
docker-lldp-sv2            latest              1825d980eafc        271 MB
docker-dhcp-relay          HEAD.781-465ebba    037f74d941cd        253.3 MB
docker-dhcp-relay          latest              037f74d941cd        253.3 MB
docker-database            HEAD.781-465ebba    9b9839843f24        251.9 MB
docker-database            latest              9b9839843f24        251.9 MB
docker-teamd               HEAD.781-465ebba    48c80858e9a6        270.9 MB
docker-teamd               latest              48c80858e9a6        270.9 MB
docker-snmp-sv2            HEAD.781-465ebba    72efa289d8a4        290.8 MB
docker-snmp-sv2            latest              72efa289d8a4        290.8 MB
docker-router-advertiser   HEAD.781-465ebba    1cfebd071d71        249.6 MB
docker-router-advertiser   latest              1cfebd071d71        249.6 MB
docker-platform-monitor    HEAD.781-465ebba    b77a2b2d1e2d        283.5 MB
docker-platform-monitor    latest              b77a2b2d1e2d        283.5 MB
docker-fpm-quagga          HEAD.781-465ebba    3d659d2da8e4        277.7 MB
docker-fpm-quagga          latest              3d659d2da8e4        277.7 MB
```
I can confirm that I experience the same issue on version _201817_ .

Here is hardware list on which I tested above configuration:
- Accton AS7816-64x (Broadcom Tomahawk II - BCM56970)
- Celestica Seastone DX010 (Broadcom Tomahawk - BCM56960)

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Can't ping from VLAN interface which has LAG member #2298

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Can't ping from VLAN interface which has LAG member #2298

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