Move proto_library from Bazel repository

Use paths.is_normalized and paths.is_absolute from bazel skylib. Upgrade skylib to latest version that has the implementation.

Use copybara for the differences in STRIC_DEPS_FLAG_TEMPLATE.

Implement native_bool_flag to read native flags and use them in proto_library. Those are implemented in such a way, that they can be replaced in place with starlark bool_flag targets.

Implement version check for PackageSpecificationInfo. It's only available after Bazel 6.4.0.

Tests will be submitted in separate PRs.

PiperOrigin-RevId: 653532601

MODULE.bazel

@@ -13,7 +13,7 @@ module(
 # https://bazel.build/versions/6.0.0/build/bzlmod#version-resolution
 # Thus the highest version in their module graph is resolved.
 bazel_dep(name = "abseil-cpp", version = "20230802.0.bcr.1", repo_name = "com_google_absl")
-bazel_dep(name = "bazel_skylib", version = "1.4.1")
+bazel_dep(name = "bazel_skylib", version = "1.7.0")
 bazel_dep(name = "jsoncpp", version = "1.9.5")
 bazel_dep(name = "rules_cc", version = "0.0.9")
 bazel_dep(name = "rules_fuzzing", version = "0.5.2")

bazel/private/BUILD.bazel

@@ -6,6 +6,7 @@
 # https://developers.google.com/open-source/licenses/bsd
 
 load("@bazel_skylib//:bzl_library.bzl", "bzl_library")
+load("//bazel/private:native_bool_flag.bzl", "native_bool_flag")
 
 licenses(["notice"])
 
@@ -52,3 +53,26 @@ bzl_library(
         "//bazel/common:proto_lang_toolchain_info_bzl",
     ],
 )
+
+native_bool_flag(
+    name = "experimental_proto_descriptor_sets_include_source_info",
+    flag = "experimental_proto_descriptor_sets_include_source_info",
+    match_value = "true",
+    visibility = ["//visibility:public"],
+)
+
+native_bool_flag(
+    name = "strict_proto_deps",
+    flag = "strict_proto_deps",
+    match_value = "off",
+    result = False,
+    visibility = ["//visibility:public"],
+)
+
+native_bool_flag(
+    name = "strict_public_imports",
+    flag = "strict_public_imports",
+    match_value = "off",
+    result = False,
+    visibility = ["//visibility:public"],
+)

bazel/private/native_bool_flag.bzl

@@ -0,0 +1,35 @@
+# Protocol Buffers - Google's data interchange format
+# Copyright 2008 Google Inc.  All rights reserved.
+#
+# Use of this source code is governed by a BSD-style
+# license that can be found in the LICENSE file or at
+# https://developers.google.com/open-source/licenses/bsd
+"""
+A helper rule that reads a native boolean flag.
+"""
+
+load("@bazel_skylib//rules:common_settings.bzl", "BuildSettingInfo")
+
+def _impl(ctx):
+    return [BuildSettingInfo(value = ctx.attr.value)]
+
+_native_bool_flag_rule = rule(
+    implementation = _impl,
+    attrs = {"value": attr.bool()},
+)
+
+def native_bool_flag(*, name, flag, match_value = "true", result = True, **kwargs):
+    _native_bool_flag_rule(
+        name = name,
+        value = select({
+            name + "_setting": result,
+            "//conditions:default": not result,
+        }),
+        **kwargs
+    )
+
+    native.config_setting(
+        name = name + "_setting",
+        values = {flag: match_value},
+        visibility = ["//visibility:private"],
+    )