Revert "[gn] Consolidate exec_script calls to speed up generation"

tools/process_gypis.py

-#!/usr/bin/env python
-# Copyright 2016, the Dart project authors.  Please see the AUTHORS file
-# for details. All rights reserved. Use of this source code is governed by a
-# BSD-style license that can be found in the LICENSE file.
-
-import gn_helpers
-import os.path
-import sys
-
-# Given a list of dart package names read in the set of runtime and sdk library
-# sources into variables in a gn scope.
-
-
-def LoadPythonDictionary(path):
-  file_string = open(path).read()
-  try:
-    file_data = eval(file_string, {'__builtins__': None}, None)
-  except SyntaxError, e:
-    e.filename = path
-    raise
-  except Exception, e:
-    raise Exception('Unexpected error while reading %s: %s' %
-                    (path, str(e)))
-
-  assert isinstance(
-    file_data, dict), '%s does not eval to a dictionary' % path
-  return file_data
-
-
-def main():
-  dart_root_dir = os.path.dirname(os.path.dirname(os.path.abspath(__file__)))
-  runtime_dir = os.path.join(dart_root_dir, 'runtime')
-  runtime_lib_dir = os.path.join(runtime_dir, 'lib')
-  sdk_lib_dir = os.path.join(dart_root_dir, 'sdk', 'lib')
-  libs = sys.argv[1:]
-  data = {}
-  data['allsources'] = []
-
-  for lib in libs:
-    runtime_path = os.path.join(runtime_lib_dir, lib + '_sources.gypi')
-    sdk_path = os.path.join(sdk_lib_dir, lib, lib + '_sources.gypi')
-    runtime_dict = LoadPythonDictionary(runtime_path)
-    for source in runtime_dict['sources']:
-      data['allsources'].append(source)
-    data[lib + '_runtime_sources'] = runtime_dict['sources']
-    sdk_dict = LoadPythonDictionary(sdk_path)
-    data[lib + '_sdk_sources'] = sdk_dict['sources']
-
-  vm_sources_path = os.path.join(runtime_dir, 'vm', 'vm_sources.gypi')
-  vm_sources_dict = LoadPythonDictionary(vm_sources_path)
-  data['vm_sources'] = vm_sources_dict['sources']
-
-  platform_sources_base = os.path.join(runtime_dir, 'platform', 'platform_')
-  platform_headers_dict = LoadPythonDictionary(
-      platform_sources_base + 'headers.gypi')
-  platform_sources_dict = LoadPythonDictionary(
-      platform_sources_base + 'sources.gypi')
-  data['platform_sources'] = platform_headers_dict[
-      'sources'] + platform_sources_dict['sources']
-
-  bin_io_sources_path = os.path.join(runtime_dir, 'bin', 'io_sources.gypi')
-  bin_io_sources_dict = LoadPythonDictionary(bin_io_sources_path)
-  data['bin_io_sources'] = bin_io_sources_dict['sources']
-
-  print gn_helpers.ToGNString(data)
-  return 0
-
-if __name__ == '__main__':
-  sys.exit(main())