record that Gamepad.buttons creates GamepadButtons

tools/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 logging
@@ skipping 530 matching lines @@
         # Unwrap the type to get the JsObject if Type is:
         #
         #    - known IDL type
         #    - type_id is None then it's probably a union type or overloaded
         #      it's a dynamic/any type
         #    - type is Object
         #
         # JsObject maybe stored in the Dart class.
         return_wrap_jso = wrap_return_type_blink(return_type, attr.type.id, self._type_registry)
     wrap_unwrap_list.append(return_wrap_jso)       # wrap_jso the returned object
-    wrap_unwrap_list.append(self._dart_use_blink) 
+    wrap_unwrap_list.append(self._dart_use_blink)
 
     # This seems to have been replaced with Custom=Getter (see above), but
     # check to be sure we don't see the old syntax
     assert(not ('CustomGetter' in attr.ext_attrs))
     native_suffix = 'Getter'
     auto_scope_setup = self._GenerateAutoSetupScope(attr.id, native_suffix)
     native_entry = \
         self.DeriveNativeEntry(attr.id, 'Getter', None)
     output_conversion = self._OutputConversion(attr.type.id, attr.id)
 
@@ skipping 69 matching lines @@
         attr_name = attr.id
       webcore_function_name = re.sub(r'^(xml|css|(?=[A-Z])|\w)',
                                      lambda s: s.group(1).upper(),
                                      attr_name)
       webcore_function_name = 'set%s' % webcore_function_name
 
     function_expression = self._GenerateWebCoreFunctionExpression(webcore_function_name, attr)
     raises = ('RaisesException' in attr.ext_attrs and
               attr.ext_attrs['RaisesException'] != 'Getter')
 
-  def AddIndexer(self, element_type):
+  def AddIndexer(self, element_type, nullable):
     """Adds all the methods required to complete implementation of List."""
     # We would like to simply inherit the implementation of everything except
     # length, [], and maybe []=.  It is possible to extend from a base
     # array implementation class only when there is no other implementation
     # inheritance.  There might be no implementation inheritance other than
     # DOMBaseWrapper for many classes, but there might be some where the
     # array-ness is introduced by a non-root interface:
     #
     #   interface Y extends X, List<T> ...
     #
@@ skipping 50 matching lines @@
     if self._HasNativeIndexSetter():
       self._EmitNativeIndexSetter(dart_element_type)
     else:
       self._members_emitter.Emit(
           '\n'
           '  void operator[]=(int index, $TYPE value) {\n'
           '    throw new UnsupportedError("Cannot assign element of immutable List.");\n'
           '  }\n',
           TYPE=dart_element_type)
 
-    self.EmitListMixin(dart_element_type)
+    self.EmitListMixin(dart_element_type, nullable)
 
   def AmendIndexer(self, element_type):
     # If interface is marked as having native indexed
     # getter or setter, we must emit overrides as it's not
     # guaranteed that the corresponding methods in C++ would be
     # virtual.  For example, as of time of writing, even though
     # Uint8ClampedArray inherits from Uint8Array, ::set method
     # is not virtual and accessing it through Uint8Array pointer
     # would lead to wrong semantics (modulo vs. clamping.)
     dart_element_type = self._DartType(element_type)
@@ skipping 525 matching lines @@
 
 def _IsCustom(op_or_attr):
   assert(isinstance(op_or_attr, IDLMember))
   return 'Custom' in op_or_attr.ext_attrs or 'DartCustom' in op_or_attr.ext_attrs
 
 def _IsCustomValue(op_or_attr, value):
   if _IsCustom(op_or_attr):
     return op_or_attr.ext_attrs.get('Custom') == value \
            or op_or_attr.ext_attrs.get('DartCustom') == value
   return False