Move hiddenapi tools used by build/soong from frameworks/base

Also, creates a python_binary_host module for generate_hiddenapi_lists
and uses that when constructing the build rule rather than using the
file directly.

Bug: 177317659
Test: m droid
      Verified that hiddenapi files (both aggregated ones and for the
      individual modules) are not affected by this change.
Change-Id: Ia11bb203ce5a74740d35f1b7e86716e15aad336e

scripts/hiddenapi/merge_csv.py

@@ -0,0 +1,69 @@
+#!/usr/bin/env python
+#
+# Copyright (C) 2018 The Android Open Source Project
+#
+# 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.
+"""
+Merge multiple CSV files, possibly with different columns.
+"""
+
+import argparse
+import csv
+import io
+
+from zipfile import ZipFile
+
+args_parser = argparse.ArgumentParser(description='Merge given CSV files into a single one.')
+args_parser.add_argument('--header', help='Comma separated field names; '
+                                          'if missing determines the header from input files.')
+args_parser.add_argument('--zip_input', help='ZIP archive with all CSV files to merge.')
+args_parser.add_argument('--output', help='Output file for merged CSV.',
+                         default='-', type=argparse.FileType('w'))
+args_parser.add_argument('files', nargs=argparse.REMAINDER)
+args = args_parser.parse_args()
+
+
+def dict_reader(input):
+    return csv.DictReader(input, delimiter=',', quotechar='|')
+
+
+if args.zip_input and len(args.files) > 0:
+    raise ValueError('Expecting either a single ZIP with CSV files'
+                     ' or a list of CSV files as input; not both.')
+
+csv_readers = []
+if len(args.files) > 0:
+    for file in args.files:
+        csv_readers.append(dict_reader(open(file, 'r')))
+elif args.zip_input:
+    with ZipFile(args.zip_input) as zip:
+        for entry in zip.namelist():
+            if entry.endswith('.uau'):
+                csv_readers.append(dict_reader(io.TextIOWrapper(zip.open(entry, 'r'))))
+
+headers = set()
+if args.header:
+    fieldnames = args.header.split(',')
+else:
+    # Build union of all columns from source files:
+    for reader in csv_readers:
+        headers = headers.union(reader.fieldnames)
+    fieldnames = sorted(headers)
+
+# Concatenate all files to output:
+writer = csv.DictWriter(args.output, delimiter=',', quotechar='|', quoting=csv.QUOTE_MINIMAL,
+                        dialect='unix', fieldnames=fieldnames)
+writer.writeheader()
+for reader in csv_readers:
+    for row in reader:
+        writer.writerow(row)