Manual merge of #14154, second try (#14264)

Something went wrong with the automated merge here as well as the first
manual merge. This is an exact export of the corresponding diff.

Differential Revision: D82127664

Author: swolchok

backends/cadence/aot/TARGETS

@@ -12,7 +12,6 @@ load(
     "CXX",
 )
 load("@fbsource//xplat/executorch/codegen:codegen.bzl", "executorch_generated_lib")
-load("@fbcode_macros//build_defs:cpp_python_extension.bzl", "cpp_python_extension")
 
 oncall("odai_jarvis")
 

exir/_serialize/TARGETS

@@ -1,11 +1,10 @@
-load("@fbcode_macros//build_defs:cpp_python_extension.bzl", "cpp_python_extension")
 load("@fbsource//xplat/executorch/build:runtime_wrapper.bzl", "runtime")
 
 oncall("executorch")
 
 # TODO(T157145817): Update other flatbuffer serializers to use flatc like
 # _flatbuffer.py does, and remove this.
-cpp_python_extension(
+runtime.cxx_python_extension(
     name = "_bindings",
     srcs = [
         "bindings.cpp",

exir/verification/TARGETS

@@ -1,10 +1,9 @@
-load("@fbcode_macros//build_defs:cpp_python_extension.bzl", "cpp_python_extension")
 load("@fbsource//xplat/executorch/build:runtime_wrapper.bzl", "runtime")
 load("@fbcode_macros//build_defs:python_unittest.bzl", "python_unittest")
 
 oncall("executorch")
 
-cpp_python_extension(
+runtime.cxx_python_extension(
     name = "bindings",
     srcs = [
         "bindings.cpp",

extension/pytree/TARGETS

@@ -1,15 +1,14 @@
 # Any targets that should be shared between fbcode and xplat must be defined in
 # targets.bzl. This file can contain fbcode-only targets.
 
-load("@fbcode_macros//build_defs:cpp_python_extension.bzl", "cpp_python_extension")
 load("@fbsource//xplat/executorch/build:runtime_wrapper.bzl", "runtime")
 load(":targets.bzl", "define_common_targets")
 
 oncall("executorch")
 
 define_common_targets()
 
-cpp_python_extension(
+runtime.cxx_python_extension(
     name = "pybindings",
     srcs = [
         "pybindings.cpp",
@@ -21,7 +20,7 @@ cpp_python_extension(
     ],
 )
 
-cpp_python_extension(
+runtime.cxx_python_extension(
     name = "pybindings_debug",
     srcs = [
         "pybindings.cpp",