CLOUDSTACK-7994: Network rules are not configured in VR after out-of-band movement due to host crash

The last commit 513adab didn't fully fix it. Scenario #1 was not handled, only #2 was handled.
Fixed #1 as part of this commit.
1. If VM is in stopped state in CS due to 'PowerMissing' report from old host (hostId is null) and then there is a 'PowerOn' report from new host
2. If VM is in running state in CS and there is a 'PowerOn' report from new host

Author: koushik-das

server/src/com/cloud/network/router/VirtualNetworkApplianceManagerImpl.java

@@ -4461,16 +4461,23 @@ public boolean preStateTransitionEvent(State oldState, VirtualMachine.Event even
     public boolean postStateTransitionEvent(State oldState, VirtualMachine.Event event, State newState, VirtualMachine vo, boolean status, Object opaque) {
         if (event == VirtualMachine.Event.FollowAgentPowerOnReport && newState == State.Running) {
             if (vo.getType() == VirtualMachine.Type.DomainRouter) {
+                // opaque -> <hostId, powerHostId>
                 if (opaque != null && opaque instanceof Pair<?, ?>) {
                     Pair<?, ?> pair = (Pair<?, ?>)opaque;
                     Object first = pair.first();
                     Object second = pair.second();
-                    if (first != null && second != null && first instanceof Long && second instanceof Long) {
-                        Long hostId = (Long)first;
+                    // powerHostId cannot be null in case of out-of-band VM movement
+                    if (second != null && second instanceof Long) {
                         Long powerHostId = (Long)second;
-                        // If VM host known to CS is different from 'PowerOn' report host, then it is out-of-band movement
-                        if (hostId.longValue() != powerHostId.longValue()) {
-                            s_logger.info("Schedule a router reboot task as router " + vo.getId() + " is powered-on out-of-band. we need to reboot to refresh network rules");
+                        Long hostId = null;
+                        if (first != null && first instanceof Long) {
+                            hostId = (Long)first;
+                        }
+                        // The following scenarios are due to out-of-band VM movement
+                        // 1. If VM is in stopped state in CS due to 'PowerMissing' report from old host (hostId is null) and then there is a 'PowerOn' report from new host
+                        // 2. If VM is in running state in CS and there is a 'PowerOn' report from new host
+                        if (hostId == null || (hostId.longValue() != powerHostId.longValue())) {
+                            s_logger.info("Schedule a router reboot task as router " + vo.getId() + " is powered-on out-of-band, need to reboot to refresh network rules");
                             _executor.schedule(new RebootTask(vo.getId()), 1000, TimeUnit.MICROSECONDS);
                         }
                     }