Test: Install vtn cord app during cord-tester setup to make it consistent with ONOS cord apps being loaded.

Don't install cord if already installed which is true when specifying external controller for setup.

When running the tester in cord mode, make sure to install cord apps after restarting ONOS on cord to bring it back to the same state as before restart.

Change-Id: If4961867f5b08c4079660961f6a30be9011b3a57
diff --git a/src/test/utils/CordTestServer.py b/src/test/utils/CordTestServer.py
index a77b977..d946acb 100644
--- a/src/test/utils/CordTestServer.py
+++ b/src/test/utils/CordTestServer.py
@@ -28,7 +28,6 @@
 
 CORD_TEST_HOST = '172.17.0.1'
 CORD_TEST_PORT = 25000
-g_onos_cord = None
 
 class QuaggaStopWrapper(Container):
     def __init__(self, name = Quagga.NAME, image = Quagga.IMAGE, tag = 'latest'):
@@ -38,8 +37,10 @@
 
 class CordTestServer(object):
 
+    onos_cord = None
+
     def __restart_onos(self, config = None):
-        if g_onos_cord:
+        if self.onos_cord:
             onos_config = '{}/network-cfg.json'.format(OnosCord.onos_config_dir)
         else:
             onos_config = '{}/network-cfg.json'.format(Onos.host_config_dir)
@@ -49,8 +50,8 @@
             except:
                 pass
         print('Restarting ONOS')
-        if g_onos_cord:
-            g_onos_cord.start(restart = True, network_cfg = config)
+        if self.onos_cord:
+            self.onos_cord.start(restart = True, network_cfg = config)
         else:
             Onos(restart = True, network_cfg = config)
         return 'DONE'
@@ -99,10 +100,9 @@
 @nottest
 def cord_test_server_start(daemonize = True, cord_test_host = CORD_TEST_HOST,
                            cord_test_port = CORD_TEST_PORT, onos_cord = None):
-    global g_onos_cord
     server = SimpleXMLRPCServer( (cord_test_host, cord_test_port) )
     server.register_instance(CordTestServer())
-    g_onos_cord = onos_cord
+    CordTestServer.onos_cord = onos_cord
     if daemonize is True:
         d = daemon.DaemonContext(files_preserve = [server],
                                  detach_process = True)