Work on blink GN bindings

Source/core/core_generated.gyp

 #
 # Copyright (C) 2013 Google Inc. All rights reserved.
 #
 # Redistribution and use in source and binary forms, with or without
 # modification, are permitted provided that the following conditions are
 # met:
 #
 #     * Redistributions of source code must retain the above copyright
 # notice, this list of conditions and the following disclaimer.
 #     * Redistributions in binary form must reproduce the above
@@ skipping 20 matching lines @@
 {
   'includes': [
     'core.gypi',
     '../bindings/bindings.gypi',
     '../build/features.gypi',
     '../build/scripts/scripts.gypi',
   ],
 
   'targets': [
     {
+      # GN version: //third_party/WebCore/Source/core:core_event_interfaces
       'target_name': 'core_event_interfaces',
       'type': 'none',
       'actions': [
         {
           'action_name': 'make_core_event_interfaces',
           'variables': {
             'event_idl_files': [
               '<@(core_event_idl_files)',
             ],
             'event_idl_files_list':
@@ skipping 16 matching lines @@
             '<(event_idl_files_list)',
             '--event-interfaces-file',
             '<(blink_core_output_dir)/EventInterfaces.in',
             '--write-file-only-if-changed',
             '<(write_file_only_if_changed)',
           ],
         },
       ],
     },
     {
+      # GN version: //third_party/WebKit/Sources/core:generated_testing_idls
       'target_name': 'generated_testing_idls',
       'type': 'none',
       'actions': [
         {
           'action_name': 'Settings',
           'inputs': [
             '<@(scripts_for_in_files)',
             '../build/scripts/make_settings.py',
             '../build/scripts/templates/InternalSettingsGenerated.idl.tmpl',
             '../build/scripts/templates/InternalSettingsGenerated.cpp.tmpl',
@@ skipping 32 matching lines @@
             'python',
             '../build/scripts/make_internal_runtime_flags.py',
             '../platform/RuntimeEnabledFeatures.in',
             '--output_dir',
             '<(blink_core_output_dir)',
           ],
         },
       ]
     },
     {
+      # GN version: //third_party/WebKit/Source/core:make_core_generated
       'target_name': 'make_core_generated',
       'type': 'none',
       'hard_dependency': 1,
       'dependencies': [
         'generated_testing_idls',
         'core_event_interfaces',
         '../config.gyp:config',
       ],
       'sources': [
         # bison rule
@@ skipping 677 matching lines @@
             '../build/scripts/rule_bison.py',
             '<(RULE_INPUT_PATH)',
             '<(blink_core_output_dir)',
             '<(bison_exe)',
           ],
         },
       ],
     },
   ],
 }