Add a namespace for ATen mode

Differential Revision: D72440313

Pull Request resolved: #9894

Author: larryliu0820

codegen/templates/RegisterCodegenUnboxedKernels.cpp

@@ -22,8 +22,8 @@
 // JIT op registry instead of c10 dispatcher. JIT op registry only takes boxed
 // kernels, so we are calling unboxing functions in UnboxingFunctions.h to cast
 // arguments into C++ types (instead of IValue) and delegate to unboxed kernels.
-using KernelSpan =
-    ::executorch::runtime::Span<const ::executorch::runtime::Kernel>;
+using KernelSpan = ::executorch::runtime::Span<
+    const ::executorch::ET_RUNTIME_NAMESPACE::Kernel>;
 namespace torch {
 namespace executor {
 namespace function {

devtools/bundled_program/bundled_program.cpp

@@ -27,9 +27,9 @@ using executorch::aten::ArrayRef;
 using executorch::aten::Half;
 using executorch::aten::ScalarType;
 using executorch::aten::Tensor;
+using ::executorch::ET_RUNTIME_NAMESPACE::Method;
 using ::executorch::runtime::Error;
 using ::executorch::runtime::EValue;
-using ::executorch::runtime::Method;
 using ::executorch::runtime::Result;
 
 namespace executorch {
@@ -332,8 +332,9 @@ ET_NODISCARD Error load_bundled_input(
         static_cast<uint32_t>(status));
   }
 
-  ::executorch::runtime::internal::event_tracer_set_bundled_input_index(
-      method.get_event_tracer(), testset_idx);
+  ::executorch::ET_RUNTIME_NAMESPACE::internal::
+      event_tracer_set_bundled_input_index(
+          method.get_event_tracer(), testset_idx);
 
   return Error::Ok;
 }