Put Dartium generated idl in a separate directory so they don't interfere with JS DOM generation.

lib/dom/scripts/fremontcutbuilder.py

 #!/usr/bin/python
 # Copyright (c) 2011, 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 database
 import databasebuilder
 import idlparser
 import logging.config
 import os.path
 import tempfile
 import sys
 
-def build_database(idl_list_file_name):
+def build_database(idl_list_file_name, database_dir):
   """This code reconstructs the FremontCut IDL database from W3C,
   WebKit and Dart IDL files."""
   current_dir = os.path.dirname(__file__)
   logging.config.fileConfig(os.path.join(current_dir, "logging.conf"))
 
-  db = database.Database(os.path.join(current_dir, '..', 'database'))
+  db = database.Database(database_dir)
 
   # Delete all existing IDLs in the DB.
   db.Delete()
 
   builder = databasebuilder.DatabaseBuilder(db)
 
   # TODO(vsm): Move this to a README.
   # This is the Dart SVN revision.
   webkit_revision = '1060'
 
@@ skipping 122 matching lines @@
   builder.merge_imported_interfaces(optional_argument_whitelist)
 
   builder.fix_displacements('WebKit')
 
   # Cleanup:
   builder.normalize_annotations(['WebKit', 'Dart'])
 
   db.Save()
 
 def main():
+  current_dir = os.path.dirname(__file__)
+
   webkit_dirs = [
     'Modules/speech',
     'Modules/indexeddb',
     'css',
     'dom',
     'fileapi',
     'Modules/filesystem',
     'html',
     'html/canvas',
     'inspector',
     'loader',
     'loader/appcache',
     'Modules/mediastream',
     'Modules/geolocation',
     'notifications',
     'page',
     'plugins',
     'storage',
     'Modules/webdatabase',
     'svg',
     'Modules/webaudio',
     'Modules/websockets',
     'workers',
     'xml',
     ]
 
   (idl_list_file, idl_list_file_name) = tempfile.mkstemp()
 
-  webcore_dir = os.path.join(os.path.dirname(__file__), '..', '..', '..',
-                              'third_party', 'WebCore')
+  webcore_dir = os.path.join(current_dir, '..', '..', '..',
+                             'third_party', 'WebCore')
   if not os.path.exists(webcore_dir):
     raise RuntimeError('directory not found: %s' % webcore_dir)
 
   def visitor(arg, dir_name, names):
     for name in names:
       file_name = os.path.join(dir_name, name)
       (interface, ext) = os.path.splitext(file_name)
       if ext == '.idl' and not name.startswith('._'):
         path = os.path.relpath(file_name, os.path.dirname(idl_list_file_name))
         os.write(idl_list_file, '%s\n' % path)
 
   for dir_name in webkit_dirs:
     dir_path = os.path.join(webcore_dir, dir_name)
     os.path.walk(dir_path, visitor, None)
 
   os.close(idl_list_file)
 
-  return build_database(idl_list_file_name)
+  database_dir = os.path.join(current_dir, '..', 'database')
+  return build_database(idl_list_file_name, database_dir)
 
 if __name__ == '__main__':
   sys.exit(main())