cronet: Create bare version of import script

This creates a very basic (and untested!) version of an import script.
Checking this in now, so we can get better history as it evolves.

import_cronet.sh can be used to invoke copybara and set the appropriate
command line arguments.

Test: ./import_cronet.sh -l 108.0.5359.128 -n 110.0.5481.65
Change-Id: I74c6aa9245e102a1f94d0630e41ddd1079e9d41f
diff --git a/Cronet/tools/import/copy.bara.sky b/Cronet/tools/import/copy.bara.sky
new file mode 100644
index 0000000..64256a0
--- /dev/null
+++ b/Cronet/tools/import/copy.bara.sky
@@ -0,0 +1,110 @@
+# Copyright 2023 Google Inc. All rights reserved.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+common_excludes = [
+    # Exclude all Android build files
+    "**/Android.bp",
+    "**/Android.mk",
+
+    # Exclude existing OWNERS files
+    "**/OWNERS",
+]
+
+cronet_origin_files = glob(
+    include = [
+        "base/**",
+        "build/**",
+        "build/buildflag.h",
+        "chrome/VERSION",
+        "components/cronet/**",
+        "components/grpc_suport/**",
+        "components/metrics/**",
+        "components/nacl/**",
+        "components/prefs/**",
+        "crypto/**",
+        "ipc/**",
+        "net/**",
+        "url/**",
+        "LICENSE",
+    ],
+    exclude = common_excludes + [
+        # Per aosp/2367109
+        "build/android/CheckInstallApk-debug.apk",
+        "build/android/unused_resources/**",
+        "build/linux/**",
+
+        # Per aosp/2374766
+        "components/cronet/ios/**",
+        "components/cronet/native/**",
+
+
+        # Exclude all third-party directories. Those are specified explicitly
+        # below, so no dependency can accidentally creep in.
+        "**/third_party/**",
+    ],
+) + glob(
+    # Explicitly include third-party dependencies.
+    # Note: some third-party dependencies include a third_party folder within
+    # them. So far, this has not become a problem.
+    include = [
+        "base/third_party/cityhash/**",
+        "base/third_party/cityhash_v103/**",
+        "base/third_party/double_conversion/**",
+        "base/third_party/dynamic_annotations/**",
+        "base/third_party/icu/**",
+        "base/third_party/nspr/**",
+        "base/third_party/superfasthash/**",
+        # TODO: we should be able to remove this dependency.
+        "base/third_party/symbolize/**",
+        "base/third_party/valgrind/**",
+        "base/third_party/xdg_user_dirs/**",
+        # Not present in source repo; requires gclient sync.
+        "buildtools/third_party/libc++/**",
+        # Not present in source repo; requires gclient sync.
+        "buildtools/third_party/libc++abi/**",
+        "net/third_party/quiche/**",
+        "net/third_party/uri_template/**",
+        "third_party/abseil-cpp/**",
+        "third_party/android_ndk/sources/android/cpufeatures/**",
+        "third_party/ashmem/**",
+        "third_party/boringssl/**",
+        "third_party/brotli/**",
+        # Not present in source repo; requires gclient sync.
+        "third_party/icu/**",
+        "third_party/libevent/**",
+        "third_party/metrics_proto/**",
+        "third_party/modp_b64/**",
+        "third_party/protobuf/**",
+        "third_party/zlib/**",
+    ],
+    exclude = common_excludes,
+)
+
+core.workflow(
+    name = "import_cronet",
+    authoring = authoring.overwrite("Cronet Mainline Eng <cronet-mainline-eng+copybara@google.com>"),
+    origin = git.origin(
+        url = "rpc://chromium/chromium/src",
+        # Source ref is set by the invoking script.
+        ref = "overwritten-by-script",
+        partial_fetch = True,
+    ),
+    origin_files = cronet_origin_files,
+    destination = git.destination(
+        # The destination URL is set by the invoking script.
+        url = "overwritten/by/script",
+        push = "upstream-import",
+    ),
+    mode = "SQUASH",
+)
diff --git a/Cronet/tools/import/import_cronet.sh b/Cronet/tools/import/import_cronet.sh
new file mode 100755
index 0000000..7642914
--- /dev/null
+++ b/Cronet/tools/import/import_cronet.sh
@@ -0,0 +1,76 @@
+#!/bin/bash
+
+# Copyright 2023 Google Inc. All rights reserved.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+# Script to invoke copybara locally to import Cronet into Android.
+# Inputs:
+#  Environment:
+#   ANDROID_BUILD_TOP: path the root of the current Android directory.
+#  Arguments:
+#   -l: The last revision that was imported.
+#   -n: The new revision to import.
+
+OPTSTRING=l:n:
+
+usage() {
+    cat <<EOF
+Usage: import_cronet.sh -l last-rev -n new-rev
+EOF
+    exit 1
+}
+
+#######################################
+# Runs the copybara import of Chromium
+# Globals:
+#   ANDROID_BUILD_TOP
+# Arguments:
+#   last_rev, string
+#   new_rev, string
+#######################################
+do_run_copybara() {
+    local _last_rev=$1
+    local _new_rev=$2
+
+    /google/bin/releases/copybara/public/copybara/copybara \
+        --git-destination-url="file://${ANDROID_BUILD_TOP}/external/cronet" \
+        --last-rev "${_last_rev}" \
+        --repo-timeout 3h \
+        "${ANDROID_BUILD_TOP}/packages/modules/Connectivity/Cronet/tools/import/copy.bara.sky" \
+        import_cronet "${_new_rev}"
+}
+
+while getopts $OPTSTRING opt; do
+    case "${opt}" in
+        l) last_rev="${OPTARG}" ;;
+        n) new_rev="${OPTARG}" ;;
+        ?) usage ;;
+        *) echo "'${opt}' '${OPTARG}'"
+    esac
+done
+
+# TODO: Get last-rev from METADATA file.
+# Setting last-rev may only be required for the first commit.
+if [ -z "${last_rev}" ]; then
+    echo "-l argument required"
+    usage
+fi
+
+if [ -z "${new_rev}" ]; then
+    echo "-n argument required"
+    usage
+fi
+
+do_run_copybara "${last_rev}" "${new_rev}"
+