Remove the TF proto rules from OSS keras.

This is the last org_tensorflow deps in keras. We replace it with py_proto_library from protobuf repo.

PiperOrigin-RevId: 364469565

WORKSPACE

@@ -20,6 +20,15 @@ http_archive(
     ],
 )
 
+http_archive(
+    name = "com_google_protobuf",
+    sha256 = "b10bf4e2d1a7586f54e64a5d9e7837e5188fc75ae69e36f215eb01def4f9721b",
+    strip_prefix = "protobuf-3.15.3",
+    urls = ["https://github.com/protocolbuffers/protobuf/archive/v3.15.3.tar.gz"],
+)
+load("@com_google_protobuf//:protobuf_deps.bzl", "protobuf_deps")
+protobuf_deps()
+
 # TF package is used as dependency for protobuf and bzl files. It is NOT used
 # for python dependency.
 http_archive(

keras/BUILD

@@ -139,7 +139,7 @@ py_library(
         "//:expect_tensorflow_installed",
         "//keras/distribute:distributed_file_utils",
         "//keras/distribute:worker_training_state",
-        "//keras/protobuf:projector_config_proto_py",
+        "//keras/protobuf:projector_config_proto_py_pb2",
         "//keras/utils:engine_utils",
         "//keras/utils:mode_keys",
     ],

keras/protobuf/BUILD

@@ -1,6 +1,7 @@
 # Description:
 #   Contains Keras protobufs
-load("@org_tensorflow//tensorflow/core/platform:build_config.bzl", "tf_proto_library")
+
+load("@com_google_protobuf//:protobuf.bzl", "py_proto_library")
 
 package(
     default_visibility = [
@@ -9,21 +10,18 @@ package(
     licenses = ["notice"],  # Apache 2.0
 )
 
-tf_proto_library(
-    name = "projector_config_proto",
-    srcs = ["projector_config.proto"],
-    cc_api_version = 2,
+py_proto_library(
+    name = "saved_metadata_proto_py_pb2",
+    srcs = ["saved_metadata.proto"],
+    deps = [":versions_proto_py_pb2"],
 )
 
-tf_proto_library(
-    name = "saved_metadata_proto",
-    srcs = ["saved_metadata.proto"],
-    cc_api_version = 2,
-    protodeps = [":versions_proto"],
+py_proto_library(
+    name = "projector_config_proto_py_pb2",
+    srcs = ["projector_config.proto"],
 )
 
-tf_proto_library(
-    name = "versions_proto",
+py_proto_library(
+    name = "versions_proto_py_pb2",
     srcs = ["versions.proto"],
-    cc_api_version = 2,
 )

keras/saving/BUILD

@@ -57,7 +57,7 @@ py_library(
         "//keras:regularizers",
         "//keras/engine:input_spec",
         "//keras/mixed_precision:autocast_variable",
-        "//keras/protobuf:saved_metadata_proto_py",
+        "//keras/protobuf:saved_metadata_proto_py_pb2",
         "//keras/saving/utils_v1",
         "//keras/utils:engine_utils",
         "//keras/utils:metrics_utils",