Clean up compute_interfaces_info.py

Source/bindings/scripts/code_generator_v8.py

 # 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
 # copyright notice, this list of conditions and the following disclaimer
@@ skipping 71 matching lines @@
 class CodeGeneratorV8(object):
     def __init__(self, interfaces_info, cache_dir):
         interfaces_info = interfaces_info or {}
         self.interfaces_info = interfaces_info
         self.jinja_env = initialize_jinja_env(cache_dir)
 
         # Set global type info
         v8_types.set_ancestors(dict(
             (interface_name, interface_info['ancestors'])
             for interface_name, interface_info in interfaces_info.iteritems()
-            if 'ancestors' in interface_info))
+            if interface_info['ancestors']))
         v8_types.set_callback_interfaces(set(
             interface_name
             for interface_name, interface_info in interfaces_info.iteritems()
             if interface_info['is_callback_interface']))
         v8_types.set_implemented_as_interfaces(dict(
             (interface_name, interface_info['implemented_as'])
             for interface_name, interface_info in interfaces_info.iteritems()
-            if 'implemented_as' in interface_info))
+            if interface_info['implemented_as']))
         v8_types.set_will_be_garbage_collected_types(set(
             interface_name
             for interface_name, interface_info in interfaces_info.iteritems()
-            if 'inherited_extended_attributes' in interface_info and
-                'WillBeGarbageCollected' in interface_info['inherited_extended_attributes']))
+            if 'WillBeGarbageCollected' in interface_info['inherited_extended_attributes']))
 
     def generate_code(self, definitions, interface_name):
         """Returns .h/.cpp code as (header_text, cpp_text)."""
         try:
             interface = definitions.interfaces[interface_name]
         except KeyError:
             raise Exception('%s not in IDL definitions' % interface_name)
 
         # Store other interfaces for introspection
         interfaces.update(definitions.interfaces)
@@ skipping 89 matching lines @@
 
     # Create a dummy file as output for the build system,
     # since filenames of individual cache files are unpredictable and opaque
     # (they are hashes of the template path, which varies based on environment)
     with open(dummy_filename, 'w') as dummy_file:
         pass  # |open| creates or touches the file
 
 
 if __name__ == '__main__':
     sys.exit(main(sys.argv))