GN: Use a custom script for package_apk() build step rather than ANT

build/android/gyp/apkbuilder.py

Index: build/android/gyp/apkbuilder.py
diff --git a/build/android/gyp/apkbuilder.py b/build/android/gyp/apkbuilder.py
new file mode 100755
index 0000000000000000000000000000000000000000..2ab568ffb067a42a2edfe7bd243d5b6ec9f02a7c
--- /dev/null
+++ b/build/android/gyp/apkbuilder.py
@@ -0,0 +1,87 @@
+#!/usr/bin/env python
+#
+# Copyright (c) 2015 The Chromium Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+"""Adds the code parts to a resource APK."""
+
+import argparse
+import os
+import shutil
+import sys
+import zipfile
+
+from util import build_utils
+
+
+def _ParseArgs(args):
+  parser = argparse.ArgumentParser()
+  build_utils.AddDepfileOption(parser)
+  parser.add_argument('--resource-apk',
+                      help='An .ap_ file built using aapt',
+                      required=True)
+  parser.add_argument('--output-apk',
+                      help='Path to the output file',
+                      required=True)
+  parser.add_argument('--dex-file',
+                      help='Path to the classes.dex to use')
+  # TODO(agrieve): Switch this to be a list of files rather than a directory.
+  parser.add_argument('--native-libs-dir',
+                      help='Directory containing native libraries to include',
+                      default=[])
+  parser.add_argument('--android-abi',
+                      help='Android architecture to use for native libraries')
+  options = parser.parse_args(args)
+  if options.native_libs_dir and not options.android_abi:
+    raise Exception('Must specify --android-abi with --native-libs-dir')
+  return options
+
+
+def _ListSubPaths(path):
+  """Returns a list of full paths to all files in the given path."""
+  return [os.path.join(path, name) for name in os.listdir(path)]
+
+
+def main(args):
+  args = build_utils.ExpandFileArgs(args)
+  options = _ParseArgs(args)
+
+  native_libs = []
+  if options.native_libs_dir:
+    native_libs = _ListSubPaths(options.native_libs_dir)
+
+  input_paths = [options.resource_apk] + native_libs
+  if options.dex_file:
+    input_paths.append(options.dex_file)
+
+  def on_stale_md5():
+    tmp_apk = options.output_apk + '.tmp'
+    try:
+      # Use a temp file to avoid creating an output if anything goes wrong.
+      shutil.copyfile(options.resource_apk, tmp_apk)
+
+      # TODO(agrieve): It would be more efficient to combine this step
+      # with finalize_apk(), which sometimes aligns and uncompresses the
+      # native libraries.
+      with zipfile.ZipFile(tmp_apk, 'a', zipfile.ZIP_DEFLATED) as apk:
+        for path in native_libs:
+          basename = os.path.basename(path)
+          apk.write(path, 'lib/%s/%s' % (options.android_abi, basename))
+        if options.dex_file:
+          apk.write(options.dex_file, 'classes.dex')
+
+      shutil.move(tmp_apk, options.output_apk)
+    finally:
+      if os.path.exists(tmp_apk):
+        os.unlink(tmp_apk)
+
+  build_utils.CallAndWriteDepfileIfStale(
+      on_stale_md5,
+      options,
+      input_paths=input_paths,
+      output_paths=[options.output_apk])
+
+
+if __name__ == '__main__':
+  main(sys.argv[1:])