Include layer GUID in SerializeToDot output

Change-Id: I1a6df60683cc51fcd9739b6dc98f1e722becf045
Signed-off-by: Robert Hughes <robert.hughes@arm.com>
diff --git a/src/armnn/Layer.cpp b/src/armnn/Layer.cpp
index 2256e48..c8d5a16 100644
--- a/src/armnn/Layer.cpp
+++ b/src/armnn/Layer.cpp
@@ -445,8 +445,13 @@
 
 void Layer::SerializeLayerParameters(ParameterStringifyFunction& fn) const
 {
+    std::string guid = std::to_string(m_Guid);
     std::string layerType = GetLayerTypeAsCString(m_Type);
     std::string backendId = std::string(m_BackendId);
+    if (!(guid.compare("") == 0) && !guid.empty())
+    {
+        fn("Guid", guid);
+    }
     if(!(m_LayerName.compare("") == 0) && !m_LayerName.empty())
     {
         fn("LayerName",m_LayerName);
diff --git a/src/backends/backendsCommon/test/OptimizedNetworkTests.cpp b/src/backends/backendsCommon/test/OptimizedNetworkTests.cpp
index c8986f5..721dfb0 100644
--- a/src/backends/backendsCommon/test/OptimizedNetworkTests.cpp
+++ b/src/backends/backendsCommon/test/OptimizedNetworkTests.cpp
@@ -50,9 +50,12 @@
         "digraph Optimized {\n"
         "    node [shape=\"record\"];\n"
         "    edge [fontsize=8 fontcolor=\"blue\" fontname=\"arial-bold\"];\n"
-        "    " << inputId << " [label=\"{Input|LayerType : Input\\lBackendID : CpuRef\\l}\"];\n"
-        "    " << addId << " [label=\"{Addition|LayerType : Addition\\lBackendID : CpuRef\\l}\"];\n"
-        "    " << outputId << " [label=\"{Output|LayerType : Output\\lBackendID : CpuRef\\l}\"];\n"
+        "    " << inputId << " [label=\"{Input|Guid : " << inputId << "\\lLayerType : Input\\l"
+                             "BackendID : CpuRef\\l}\"];\n"
+        "    " << addId << " [label=\"{Addition|Guid : " << addId << "\\lLayerType : Addition\\l"
+                           "BackendID : CpuRef\\l}\"];\n"
+        "    " << outputId << " [label=\"{Output|Guid : " << outputId << "\\lLayerType : Output\\l"
+                              "BackendID : CpuRef\\l}\"];\n"
         "    " << inputId << " -> " << addId << " [label=< [4] >];\n"
         "    " << inputId << " -> " << addId << " [label=< [4] >];\n"
         "    " << addId << " -> " << outputId << " [label=< [4] >];\n"