Expose a test related internal API for keras.

The layer_test will be used by keras-cv/nlp and tf-addons.

PiperOrigin-RevId: 427277621

keras/BUILD

@@ -59,6 +59,7 @@ py_library(
         "//keras/preprocessing",
         "//keras/saving",
         "//keras/testing_infra:keras_doctest_lib",
+        "//keras/testing_infra:test_utils",  # For keras.__internal__ API
         "//keras/utils",
         "//keras/wrappers",
     ],

keras/api/BUILD

@@ -114,6 +114,7 @@ keras_packages = [
     "keras.saving.model_config",
     "keras.saving.save",
     "keras.saving.saved_model_experimental",
+    "keras.testing_infra.test_utils",
     "keras.utils.data_utils",
     "keras.utils.generic_utils",
     "keras.utils.io_utils",

keras/api/golden/v2/tensorflow.keras.__internal__.utils.pbtxt

@@ -1,5 +1,9 @@
 path: "tensorflow.keras.__internal__.utils"
 tf_module {
+  member_method {
+    name: "layer_test"
+    argspec: "args=[\'self\'], varargs=args, keywords=kwargs, defaults=None"
+  }
   member_method {
     name: "register_symbolic_tensor_type"
     argspec: "args=[\'cls\'], varargs=None, keywords=None, defaults=None"

keras/testing_infra/test_utils.py

@@ -37,6 +37,7 @@
 import numpy as np
 import tensorflow.compat.v2 as tf
 from tensorflow.python.framework import test_util as tf_test_utils  # pylint: disable=g-direct-tensorflow-import
+from tensorflow.python.util.tf_export import keras_export  # pylint: disable=g-direct-tensorflow-import
 
 
 def string_test(actual, expected):
@@ -76,6 +77,7 @@ def get_test_data(train_samples,
           (x[train_samples:], y[train_samples:]))
 
 
+@keras_export('keras.__internal__.utils.layer_test', v1=[])
 @tf_test_utils.disable_cudnn_autotune
 def layer_test(layer_cls,
                kwargs=None,