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

extension/module/bundled_module.h

@@ -16,12 +16,12 @@
 #define ET_BUNDLED_MODULE_NAMESPACE bundled_module
 #endif // USE_ATEN_LIB
 
-using executorch::extension::ET_MODULE_NAMESPACE::Module;
-
 namespace executorch {
 namespace extension {
 namespace ET_BUNDLED_MODULE_NAMESPACE {
 
+using executorch::extension::ET_MODULE_NAMESPACE::Module;
+
 /**
  * A facade class for loading bundled programs and executing methods within
  * them.

extension/module/module.h

@@ -24,13 +24,16 @@
 
 namespace executorch {
 namespace extension {
-namespace ET_MODULE_NAMESPACE {
 
 using ET_RUNTIME_NAMESPACE::Method;
 using ET_RUNTIME_NAMESPACE::MethodMeta;
 using ET_RUNTIME_NAMESPACE::NamedDataMap;
 using ET_RUNTIME_NAMESPACE::Program;
 
+class ExecuTorchJni;
+
+namespace ET_MODULE_NAMESPACE {
+
 /**
  * A facade class for loading programs and executing methods within them.
  */
@@ -500,7 +503,7 @@ class Module {
  protected:
   std::unordered_map<std::string, MethodHolder> methods_;
 
-  friend class ExecuTorchJni;
+  friend class executorch::extension::ExecuTorchJni;
 };
 
 } // namespace ET_MODULE_NAMESPACE
@@ -518,6 +521,6 @@ using ::executorch::extension::ET_MODULE_NAMESPACE::Module;
 namespace executorch {
 namespace extension {
 // backward compatible namespace alias
-using namespace ::executorch::extension::ET_MODULE_NAMESPACE;
+using ::executorch::extension::ET_MODULE_NAMESPACE::Module;
 } // namespace extension
 } // namespace executorch