LiveMerge: move getVolumeInfo to executeCommand

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

@@ -60,6 +60,8 @@ protected void executeCommand() {
         // Let doPolling() drive the execution; we don't have any guarantee that
         // executeCommand() will finish before doPolling() is called, and we don't
         // want to possibly run the first command twice.
+        getParameters().setCommandStep(getInitialMergeStepForImage(getParameters().getImageId()));
+        getParameters().setChildCommands(new HashMap<>());
         setSucceeded(true); // Allow runAction to succeed
     }
 
@@ -83,17 +85,12 @@ public boolean ignoreChildCommandFailure() {
 
     @Override
     public boolean performNextOperation(int completedChildCount) {
-
         // Steps are executed such that:
         //  a) all logic before the command runs is idempotent
         //  b) the command is the last action in the step
         // This allows for recovery after a crash at any point during command execution.
 
         log.debug("Proceeding with execution of RemoveSnapshotSingleDiskLiveCommand");
-        if (getParameters().getCommandStep() == null) {
-            getParameters().setCommandStep(getInitialMergeStepForImage(getParameters().getImageId()));
-            getParameters().setChildCommands(new HashMap<>());
-        }
 
         // Upon recovery or after invoking a new child command, our map may be missing an entry
         syncChildCommandList(getParameters());