Refactor Forced Import

 * Find and replace all workloads associated with imported IO
 * Only attempt tensorhandle replacement if supported by all workloads
 * Add new RefBaseWorkload to enable forced input for ref backend
 * Store imported tensorhandles in preImportedTensorhandles instead of outputHandles
 * Create pre-imported tensorhandles at network load-time
 * Front load import workload validation to load network time
 * Only call ReplaceTensorHandle when needed

Change-Id: I3816a71b7f57ae90388bb16462a75d4ef3544fa7
Signed-off-by: Finn Williams <finn.williams@arm.com>
diff --git a/src/backends/reference/workloads/RefElementwiseWorkload.hpp b/src/backends/reference/workloads/RefElementwiseWorkload.hpp
index 4b108e4..065a783 100644
--- a/src/backends/reference/workloads/RefElementwiseWorkload.hpp
+++ b/src/backends/reference/workloads/RefElementwiseWorkload.hpp
@@ -6,7 +6,7 @@
 #pragma once
 
 #include <armnn/Types.hpp>
-#include <armnn/backends/Workload.hpp>
+#include "RefBaseWorkload.hpp"
 #include <armnn/backends/WorkloadData.hpp>
 #include "BaseIterator.hpp"
 #include "ElementwiseFunction.hpp"
@@ -18,12 +18,12 @@
 {
 
 template <typename Functor, typename ParentDescriptor, typename armnn::StringMapping::Id DebugString>
-class RefElementwiseWorkload : public BaseWorkload<ParentDescriptor>
+class RefElementwiseWorkload : public RefBaseWorkload<ParentDescriptor>
 {
 public:
     using InType = typename ElementwiseBinaryFunction<Functor>::InType;
     using OutType = typename ElementwiseBinaryFunction<Functor>::OutType;
-    using BaseWorkload<ParentDescriptor>::m_Data;
+    using RefBaseWorkload<ParentDescriptor>::m_Data;
 
     RefElementwiseWorkload(const ParentDescriptor& descriptor, const WorkloadInfo& info);
     void Execute() const override;