IDL: Drop redundant null check for string and wrapper type attributes

Source/bindings/scripts/v8_attributes.py

 # Copyright (C) 2013 Google Inc. All rights reserved.
 #
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 # modification, are permitted provided that the following conditions are
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 #     * Redistributions of source code must retain the above copyright
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@@ skipping 76 matching lines @@
         'activity_logging_world_list_for_getter': v8_utilities.activity_logging_world_list(attribute, 'Getter'),  # [ActivityLogging]
         'activity_logging_world_list_for_setter': v8_utilities.activity_logging_world_list(attribute, 'Setter'),  # [ActivityLogging]
         'activity_logging_include_old_value_for_setter': 'LogPreviousValue' in extended_attributes,  # [ActivityLogging]
         'activity_logging_world_check': v8_utilities.activity_logging_world_check(attribute),  # [ActivityLogging]
         'cached_attribute_validation_method': extended_attributes.get('CachedAttribute'),
         'conditional_string': v8_utilities.conditional_string(attribute),
         'constructor_type': idl_type.constructor_type_name
                             if is_constructor_attribute(attribute) else None,
         'cpp_name': cpp_name(attribute),
         'cpp_type': idl_type.cpp_type,
         'cpp_value_to_v8_value': idl_type.cpp_value_to_v8_value(cpp_value='original', creation_context='info.Holder()'),

[Jens Widell, 2014/07/01 06:43:22]

Dropped this because it's overridden by getter_context() anyway, with the right
cpp_value ('cppValue' instead of 'original').

It wouldn't be overridden for an attribute with a custom getter, but I think
it's a safe to assume that we won't need this in a setter for an attribute with
a custom getter. (This expression is essentially a low-level getter call most of
the time, and it seems wrong to generate that code for an attribute with a
custom getter anyway.)

         'deprecate_as': v8_utilities.deprecate_as(attribute),  # [DeprecateAs]
         'enum_validation_expression': idl_type.enum_validation_expression,
         'has_custom_getter': has_custom_getter,
         'has_custom_setter': has_custom_setter,
         'has_type_checking_unrestricted': has_type_checking_unrestricted,
         'idl_type': str(idl_type),  # need trailing [] on array for Dictionary::ConversionContext::setConversionType
         'is_call_with_execution_context': v8_utilities.has_extended_attribute_value(attribute, 'CallWith', 'ExecutionContext'),
         'is_call_with_script_state': v8_utilities.has_extended_attribute_value(attribute, 'CallWith', 'ScriptState'),
         'is_check_security_for_node': is_check_security_for_node,
         'is_custom_element_callbacks': is_custom_element_callbacks,
@@ skipping 55 matching lines @@
     extended_attributes = attribute.extended_attributes
 
     cpp_value = getter_expression(interface, attribute, context)
     # Normally we can inline the function call into the return statement to
     # avoid the overhead of using a Ref<> temporary, but for some cases
     # (nullable types, EventHandler, [CachedAttribute], or if there are
     # exceptions), we need to use a local variable.
     # FIXME: check if compilers are smart enough to inline this, and if so,
     # always use a local variable (for readability and CG simplicity).
     release = False
-    if (idl_type.is_nullable or
+    if ((idl_type.is_nullable and not context['is_nullable_simple']) or
         base_idl_type == 'EventHandler' or
         'CachedAttribute' in extended_attributes or
         'ReflectOnly' in extended_attributes or
         context['is_keep_alive_for_gc'] or
         context['is_getter_raises_exception']):
         context['cpp_value_original'] = cpp_value
         cpp_value = 'cppValue'
         # EventHandler has special handling
         if base_idl_type != 'EventHandler' and idl_type.is_interface_type:
             release = True
@@ skipping 248 matching lines @@
     lambda self: strip_suffix(self.base_type, 'Constructor'))
 
 
 def is_constructor_attribute(attribute):
     # FIXME: replace this with [ConstructorAttribute] extended attribute
     return attribute.idl_type.base_type.endswith('Constructor')
 
 
 def constructor_getter_context(interface, attribute, context):
     context['needs_constructor_getter_callback'] = context['measure_as'] or context['deprecate_as']