Fix transpose of empty initializers called from constant folding (microsoft#25922)

### Description

ConstantFolding crashes when a constant empty initializer is transposed.

### Motivation and Context

This rare case happened when converting a LLM into onnx with static
shape.

Author: xadupre

onnxruntime/core/optimizer/transpose_optimization/ort_optimizer_api_impl.cc

@@ -575,7 +575,9 @@ void ApiGraph::TransposeInitializer(std::string_view name, const std::vector<int
   TensorShape new_tensor_shape(new_tensor_shape_dims);
   Tensor out_tensor(tensor_dtype, new_tensor_shape, cpu_allocator_);
 
-  ORT_THROW_IF_ERROR(Transpose::DoTranspose(permutations, in_tensor, out_tensor));
+  if (new_tensor_shape.Size() > 0) {
+    ORT_THROW_IF_ERROR(Transpose::DoTranspose(permutations, in_tensor, out_tensor));
+  }
 
   auto& node_arg = *graph_.GetNodeArg(name_str);
   TensorShapeProto new_shape;

onnxruntime/test/optimizer/graph_transform_test.cc

@@ -631,6 +631,24 @@ TEST_F(GraphTransformationTests, ConstantFoldingNodesOnDifferentEP) {
   }
 }
 
+TEST_F(GraphTransformationTests, ConstantFoldingTransposeEmptyInitializer) {
+  constexpr const ORTCHAR_T* model_uri = MODEL_FOLDER "constant_folding_transpose_empty_initializer.onnx";
+  std::shared_ptr<Model> model;
+  ASSERT_STATUS_OK(Model::Load(model_uri, model, nullptr, *logger_));
+  Graph& graph = model->MainGraph();
+  std::map<std::string, int> op_to_count = CountOpsInGraph(graph);
+  ASSERT_TRUE(op_to_count["Transpose"] == 1);
+  std::unique_ptr<CPUExecutionProvider> e = std::make_unique<CPUExecutionProvider>(CPUExecutionProviderInfo());
+  onnxruntime::GraphTransformerManager graph_transformation_mgr{5};
+  const ConfigOptions empty_config_options;
+  ASSERT_STATUS_OK(graph_transformation_mgr.Register(
+      std::make_unique<ConstantFolding>(*e.get(), false /*skip_dequantize_linear*/, empty_config_options),
+      TransformerLevel::Level1));
+  ASSERT_STATUS_OK(graph_transformation_mgr.ApplyTransformers(graph, TransformerLevel::Level1, *logger_));
+  op_to_count = CountOpsInGraph(graph);
+  ASSERT_TRUE(op_to_count["Transpose"] == 0);
+}
+
 TEST_F(GraphTransformationTests, ConstantFoldingUnsupportedFloat16) {
   constexpr const ORTCHAR_T* model_uri = MODEL_FOLDER "constant_float16_mul.onnx";
   std::shared_ptr<Model> model;