Reapply/merge derived_sources.gyp useless use of cat (demoggification)

Source/bindings/derived_sources.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 135 matching lines @@
       'action_name': 'compute_interface_dependencies',
       'variables': {
         # Write sources into a file, so that the action command line won't
         # exceed OS limits.
         'main_idl_files_list': '<|(main_idl_files_list.tmp <@(main_idl_files))',
         'support_idl_files_list': '<|(support_idl_files_list.tmp <@(support_idl_files))',
       },
       'inputs': [
         'scripts/compute_dependencies.py',
         '<(main_idl_files_list)',
-        '<!@(cat <(main_idl_files_list))',
+        '<@(main_idl_files)',
         '<(support_idl_files_list)',
-        '<!@(cat <(support_idl_files_list))',
+        '<@(support_idl_files)',
        ],
        'outputs': [
          '<(SHARED_INTERMEDIATE_DIR)/blink/InterfaceDependencies.txt',
          '<(SHARED_INTERMEDIATE_DIR)/blink/BindingsDerivedSources.txt',
          '<@(generated_global_constructors_idl_files)',
          '<(SHARED_INTERMEDIATE_DIR)/blink/EventInterfaces.in',
        ],
        'msvs_cygwin_shell': 0,
        'action': [
          'python',
@@ skipping 124 matching lines @@
           '../build/scripts/action_derivedsourcesallinone.py',
           '<(SHARED_INTERMEDIATE_DIR)/blink/BindingsDerivedSources.txt',
           '--',
           '<@(derived_sources_aggregate_files)',
         ],
         'message': 'Generating bindings derived sources',
       }],
     },
   ],
 }