IVGCVSW-2315 Add DebugLayer and no-op factory method

Change-Id: I5455b720565248ff94278e76887d63f8434a7b58
diff --git a/src/backends/backendsCommon/WorkloadData.hpp b/src/backends/backendsCommon/WorkloadData.hpp
index 7b96bbc..ee1a054 100644
--- a/src/backends/backendsCommon/WorkloadData.hpp
+++ b/src/backends/backendsCommon/WorkloadData.hpp
@@ -356,4 +356,9 @@
     void Validate(const WorkloadInfo& workloadInfo) const;
 };
 
+struct DebugQueueDescriptor : QueueDescriptor
+{
+    void Validate(const WorkloadInfo& workloadInfo) const;
+};
+
 } //namespace armnn