core: fix checking if an active snapshot is set with memory for resto…

…ring purpose

This is a followup fix for
oVirt#653 (based on a comment review).
by including the metadata volumes (in addition to memory ones) when checking if
an active snapshot is set with memory for restoring.

backend/manager/modules/bll/src/main/java/org/ovirt/engine/core/bll/snapshots/TryBackToAllSnapshotsOfVmCommand.java

@@ -219,7 +219,7 @@ private void restoreVmConfigFromSnapshot() {
                 getCompensationContext(),
                 getCurrentUser(),
                 new VmInterfaceManager(getMacPool()),
-                snapshot.getMemoryDiskId() != null);
+                snapshot.containsMemory());
 
         // custom preview - without leases
         if (!getParameters().isRestoreLease()) {