Description of problem:
net-event should not report unsuccessful event

Version-Release number of selected component (if applicable):
libvirt-1.2.8-6.el7.x86_64

How reproducible:
100%

Steps:
1.prepare a virtual network
# virsh net-list --all
 Name                 State      Autostart     Persistent
----------------------------------------------------------
 default              active     yes           yes



2.# virsh net-event net4 lifecycle --loop

3.open another terminal
[root@localhost lhaung]# virsh net-start default
error: Failed to start network default
error: Requested operation is not valid: network is already active

[root@localhost lhaung]# virsh net-start default
error: Failed to start network default
error: Requested operation is not valid: network is already active

4.from the first terminal
event 'lifecycle' for network default: Started
event 'lifecycle' for network default: Started



Actual results:
net-event output a unsuccessful event

Expected results:
net-event should  not report unsuccessful event

Additional info:

upstream patch:

commit 45d9ea5cddad5ed151db15362a881b730b8c88f1
Author: Luyao Huang <lhuang@redhat.com>
Date:   Sat Nov 1 18:03:23 2014 +0800

    network: fix call virNetworkEventLifecycleNew when networkStartNetwork fail
    
    When start a network fail, libvirt still call virNetworkEventLifecycleNew
    to send a event.
    
    Signed-off-by: Luyao Huang <lhuang@redhat.com>

diff --git a/src/network/bridge_driver.c b/src/network/bridge_driver.c
index 10ded33..11e86e0 100644
--- a/src/network/bridge_driver.c
+++ b/src/network/bridge_driver.c
@@ -3253,7 +3253,8 @@ static int networkCreate(virNetworkPtr net)
     if (virNetworkCreateEnsureACL(net->conn, network->def) < 0)
         goto cleanup;
 
-    ret = networkStartNetwork(driver, network);
+    if ((ret = networkStartNetwork(driver, network)) < 0)
+        goto cleanup;
 
     event = virNetworkEventLifecycleNew(network->def->name,
                                         network->def->uuid,