Signed-off-by: Stepan Ermakov <[email protected]>

##Fixes issue
This PR fixes the oVirt#900 issue.

##Changes introduced with this PR
Since the SecretValue structure is used in GWT, it should implement Serializable interface.
Also couple null checks were added to avoid NPE in the scenario explained in the oVirt#900 issue.

##Are you the owner of the code you are sending in, or do you have permission of the owner?
Yes

backend/manager/modules/common/src/main/java/org/ovirt/engine/core/common/utils/SecretValue.java

@@ -1,8 +1,11 @@
 package org.ovirt.engine.core.common.utils;
 
+import java.io.Serializable;
 import java.util.Objects;
 
-public class SecretValue<T> {
+public class SecretValue<T> implements Serializable {
+    private static final long serialVersionUID = -7894728002078425194L;
+
     private T value;
 
     public T getValue() {

frontend/webadmin/modules/gwt-common/src/main/java/org/ovirt/engine/ui/common/widget/uicommon/vm/VmSnapshotInfoPanel.java

@@ -1,10 +1,14 @@
 package org.ovirt.engine.ui.common.widget.uicommon.vm;
 
+import java.math.BigInteger;
 import java.util.ArrayList;
 import java.util.Date;
 import java.util.List;
+import java.util.Optional;
 
 import org.gwtbootstrap3.client.ui.Label;
+import org.ovirt.engine.core.common.businessentities.network.NetworkInterface;
+import org.ovirt.engine.core.common.businessentities.network.NetworkStatistics;
 import org.ovirt.engine.core.common.businessentities.network.VmInterfaceType;
 import org.ovirt.engine.core.common.businessentities.network.VmNetworkInterface;
 import org.ovirt.engine.core.common.businessentities.storage.Disk;
@@ -266,8 +270,10 @@ protected Double getSpeed(VmNetworkInterface object) {
         AbstractTextColumn<VmNetworkInterface> dropsColumn = new AbstractSumUpColumn<VmNetworkInterface>() {
             @Override
             protected Double[] getRawValue(VmNetworkInterface object) {
-                Double receiveDrops = object != null ? object.getStatistics().getReceiveDrops().doubleValue() : null;
-                Double transmitDrops = object != null ? object.getStatistics().getTransmitDrops().doubleValue() : null;
+                Double receiveDrops = Optional.ofNullable(object).map(NetworkInterface::getStatistics)
+                        .map(NetworkStatistics::getReceiveDrops).map(BigInteger::doubleValue).orElse(null);
+                Double transmitDrops = Optional.ofNullable(object).map(NetworkInterface::getStatistics)
+                        .map(NetworkStatistics::getTransmitDrops).map(BigInteger::doubleValue).orElse(null);
                 return new Double[] { receiveDrops, transmitDrops };
             }
         };