IVGCVSW-6119 ConstTensorsAsInput: FullyConnected

 * Constant weights and biases are now stored as Constant layers.
 * Updated Serializer, Deserializer and unit tests to reflect this.
 * Updated TfLiteDelegate, TfLiteParser and OnnxParser.
 * Updated Schema with IsConstant and ConstantTensorsAsInputs.
 * Updated Ref backend to handle constant weights and
   bias as inputs rather than reading from member variables.
 * Added dynamic or constant input EndToEnd tests.

!android-nn-driver:5959

Signed-off-by: Matthew Sloyan <matthew.sloyan@arm.com>
Change-Id: Ibf3cf437df1100e4b322b0d303c575c6339f9696
diff --git a/src/backends/reference/RefBackend.hpp b/src/backends/reference/RefBackend.hpp
index 441f4eb..2855957 100644
--- a/src/backends/reference/RefBackend.hpp
+++ b/src/backends/reference/RefBackend.hpp
@@ -12,7 +12,8 @@
 const BackendCapabilities cpuRefCapabilities("CpuRef",
                                              {
                                                     {"NonConstWeights", true},
-                                                    {"AsyncExecution", true}
+                                                    {"AsyncExecution", true},
+                                                    {"ConstantTensorsAsInputs", true}
                                              });
 
 const std::set<armnn::BackendCapability> oldCpuRefCapabilities {