Restore forgotten negation.

lib/dom/scripts/systemnative.py

 #!/usr/bin/python
 # Copyright (c) 2012, 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.
 
 """This module provides shared functionality for the systems to generate
 native binding from the IDL database."""
 
 import emitter
 import os
@@ skipping 291 matching lines @@
     function_expression = '%s::%s' % (self._interface_type_info.native_type(), create_function)
     invocation = self._GenerateWebCoreInvocation(function_expression, arguments,
         self._interface.id, self._interface.ext_attrs, raises_dom_exceptions)
 
     runtime_check = None
     database = self._system._database
     if 'synthesizedV8EnabledPerContext' in self._interface.ext_attrs:
       raises_exceptions = True
       self._cpp_impl_includes.add('"ContextFeatures.h"')
       runtime_check = emitter.Format(
-          '        if (ContextFeatures::$(FEATURE)Enabled(DartUtilities::domWindowForCurrentIsolate()->document())) {\n'
+          '        if (!ContextFeatures::$(FEATURE)Enabled(DartUtilities::domWindowForCurrentIsolate()->document())) {\n'
           '            exception = Dart_NewString("Feature $FEATURE is not enabled");\n'
           '            goto fail;\n'
           '        }',
           FEATURE=self._interface.ext_attrs['synthesizedV8EnabledPerContext'])
 
     self._GenerateNativeCallback(callback_name='constructorCallback',
         parameter_definitions=parameter_definitions_emitter.Fragments(),
         needs_receiver=False, invocation=invocation,
         raises_exceptions=raises_exceptions,
         runtime_check=runtime_check)
@@ skipping 749 matching lines @@
       continue
     parent_interface = database.GetInterface(parent.type.id)
     if callback(parent_interface):
       return parent_interface
     parent_interface = _FindParent(parent_interface, database, callback)
     if parent_interface:
       return parent_interface
 
 def _IsArgumentOptionalInWebCore(argument):
   return IsOptional(argument) and not 'Callback' in argument.ext_attrs