Support more configurability in GN toolchains

tools/gn/BUILD.gn

 # Copyright (c) 2013 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.
 
 defines = [ "GN_BUILD" ]
 
 static_library("gn_lib") {
   sources = [
     "action_target_generator.cc",
     "action_target_generator.h",
@@ skipping 75 matching lines @@
     "ninja_action_target_writer.cc",
     "ninja_action_target_writer.h",
     "ninja_binary_target_writer.cc",
     "ninja_binary_target_writer.h",
     "ninja_build_writer.cc",
     "ninja_build_writer.h",
     "ninja_copy_target_writer.cc",
     "ninja_copy_target_writer.h",
     "ninja_group_target_writer.cc",
     "ninja_group_target_writer.h",
-    "ninja_helper.cc",
-    "ninja_helper.h",
+    "ninja_utils.cc",
+    "ninja_utils.h",
     "ninja_target_writer.cc",
     "ninja_target_writer.h",
     "ninja_toolchain_writer.cc",
     "ninja_toolchain_writer.h",
     "ninja_writer.cc",
     "ninja_writer.h",
     "operators.cc",
     "operators.h",
+    "output_file.cc",
     "output_file.h",
     "parse_tree.cc",
     "parse_tree.h",
     "parser.cc",
     "parser.h",
     "path_output.cc",
     "path_output.h",
     "pattern.cc",
     "pattern.h",
     "scheduler.cc",
     "scheduler.h",
     "scope.cc",
     "scope.h",
     "scope_per_file_provider.cc",
     "scope_per_file_provider.h",
     "settings.cc",
     "settings.h",
     "setup.cc",
     "setup.h",
     "source_dir.cc",
     "source_dir.h",
     "source_file.cc",
     "source_file.h",
+    "source_file_type.cc",
+    "source_file_type.h",
     "standard_out.cc",
     "standard_out.h",
     "string_utils.cc",
     "string_utils.h",
     "substitution_list.cc",
     "substitution_list.h",
     "substitution_pattern.cc",
     "substitution_pattern.h",
     "substitution_type.cc",
     "substitution_type.h",
     "substitution_writer.cc",
     "substitution_writer.h",
     "target.cc",
     "target.h",
     "target_generator.cc",
     "target_generator.h",
     "template.cc",
     "template.h",
     "token.cc",
     "token.h",
     "tokenizer.cc",
+    "tool.cc",
+    "tool.h",
     "tokenizer.h",
     "toolchain.cc",
     "toolchain.h",
     "trace.cc",
     "trace.h",
     "unique_vector.h",
     "value.cc",
     "value.h",
     "value_extractors.cc",
     "value_extractors.h",
@@ skipping 37 matching lines @@
     "function_write_file_unittest.cc",
     "functions_target_unittest.cc",
     "functions_unittest.cc",
     "header_checker_unittest.cc",
     "input_conversion_unittest.cc",
     "label_unittest.cc",
     "loader_unittest.cc",
     "ninja_action_target_writer_unittest.cc",
     "ninja_binary_target_writer_unittest.cc",
     "ninja_copy_target_writer_unittest.cc",
-    "ninja_helper_unittest.cc",
     "ninja_target_writer_unittest.cc",
+    "ninja_toolchain_writer_unittest.cc",
     "operators_unittest.cc",
     "parse_tree_unittest.cc",
     "parser_unittest.cc",
     "path_output_unittest.cc",
     "pattern_unittest.cc",
     "run_all_unittests.cc",
     "scope_per_file_provider_unittest.cc",
     "scope_unittest.cc",
     "source_dir_unittest.cc",
     "string_utils_unittest.cc",
@@ skipping 13 matching lines @@
     ":gn_lib",
     "//base/test:test_support",
     "//testing/gtest",
   ]
 }
 
 executable("generate_test_gn_data") {
   sources = [ "generate_test_gn_data.cc" ]
   deps = [ "//base" ]
 }