IVGCVSW-3418 Add Arm NN front end support for the new Stack layer

 * Added new StackLayer class
 * Made necessary changes to Descriptors, ILayerSupport, ILayerVisitor, etc.
 * Added unit tests

Signed-off-by: Matthew Jackson <matthew.jackson@arm.com>
Change-Id: Ieb97a928a342ffe1901c6058eb895711c358fd3d
diff --git a/src/armnnSerializer/Serializer.hpp b/src/armnnSerializer/Serializer.hpp
index 0383d105..8404a7f 100644
--- a/src/armnnSerializer/Serializer.hpp
+++ b/src/armnnSerializer/Serializer.hpp
@@ -202,6 +202,10 @@
                             const armnn::ViewsDescriptor& viewsDescriptor,
                             const char* name = nullptr) override;
 
+    void VisitStackLayer(const armnn::IConnectableLayer* layer,
+                         const armnn::StackDescriptor& stackDescriptor,
+                         const char* name = nullptr) override;
+
     void VisitStridedSliceLayer(const armnn::IConnectableLayer* layer,
                                 const armnn::StridedSliceDescriptor& stridedSliceDescriptor,
                                 const char* name = nullptr) override;