Update on "[ExecuTorch][#10375] Add extension.BundledModule to Wrap extension.Module with Bundled Program Logic"

#10375

# Context

This issue is a step of #9638.

In #9638, we want to have `extension.Module` as the single source of implementation in `pybindings`, which means that `pybindings.PyModule` should use `extension.Module` rather than its own `pybindings.Module`.

The issue is that `pybindings.PyModule` is dependent on the `method` getter from `pybindings.Module`, which `extension.Module` do not have. Since we don't want to expose `method` getter in `extension.Module`, we have to protect the getter, wrap the functions that is dependent on it and use the protected getter there, ultimately decouple `pybindings` from a `method` getter.

# Proposal

Now that we have a protected `method` getter, we can introduce a `extension.BundledModule`, a child class inheriting `extension.Module` which wraps up bundled program logic that is dependent on the `method` getter.

Differential Revision: [D73564125](https://our.internmc.facebook.com/intern/diff/D73564125/)

[ghstack-poisoned]

Author: zhenyan-zhang-meta

devtools/bundled_program/bundled_program.cpp

@@ -267,7 +267,9 @@ ET_NODISCARD Error load_bundled_input(
       "testset_idx %zu is out of range [0, %u]",
       testset_idx,
       test_cases->size());
-  auto bundled_inputs = test_cases->Get(static_cast<flatbuffers::uoffset_t>(testset_idx))->inputs();
+  auto bundled_inputs =
+      test_cases->Get(static_cast<flatbuffers::uoffset_t>(testset_idx))
+          ->inputs();
 
   for (size_t input_idx = 0; input_idx < method.inputs_size(); input_idx++) {
     auto bundled_input = bundled_inputs->GetMutableObject(input_idx);
@@ -372,7 +374,8 @@ ET_NODISCARD Error verify_method_outputs(
       testset_idx,
       test_cases->size());
   auto bundled_expected_outputs =
-      test_cases->Get(static_cast<flatbuffers::uoffset_t>(testset_idx))->expected_outputs();
+      test_cases->Get(static_cast<flatbuffers::uoffset_t>(testset_idx))
+          ->expected_outputs();
 
   if (bundled_expected_outputs->size() == 0) {
     // No bundled expected outputs, so we can't verify the method outputs.