[bindings] Eliminate custom bindings for DeviceOrientationEvent.

Source/bindings/templates/methods.cpp

 {% from 'conversions.cpp' import declare_enum_validation_variable, v8_value_to_local_cpp_value %}
 
 
 {##############################################################################}
 {% macro generate_method(method, world_suffix) %}
 {% filter conditional(method.conditional_string) %}
 {% if method.returns_promise and method.has_exception_state %}
 static void {{method.name}}{{method.overload_index}}Method{{world_suffix}}Promise(const v8::FunctionCallbackInfo<v8::Value>& info, ExceptionState& exceptionState)
 {% else %}
 static void {{method.name}}{{method.overload_index}}Method{{world_suffix}}(const v8::FunctionCallbackInfo<v8::Value>& info)
@@ skipping 65 matching lines @@
 {{generate_argument_var_declaration(argument)}};
 {% endfor %}
 {
     {% for argument in method.arguments %}
     {% if argument.set_default_value %}
     if (!info[{{argument.index}}]->IsUndefined()) {
         {{generate_argument(method, argument, world_suffix) | indent(8)}}
     } else {
         {{argument.set_default_value}};
     }
+    {% elif argument.is_undefined_to_null %}
+    if (!isUndefinedOrNull(info[{{argument.index}}])) {
+        {{generate_argument(method, argument, world_suffix) | indent(8)}}
+    }
     {% else %}
     {{generate_argument(method, argument, world_suffix) | indent}}
     {% endif %}
     {% endfor %}
 }
 {% endmacro %}
 
 
 {######################################}
 {% macro generate_argument_var_declaration(argument) %}
 {# FIXME: remove EventListener special case #}
 {% if argument.idl_type == 'EventListener' %}
 RefPtr<{{argument.idl_type}}> {{argument.name}}
+{% elif argument.is_undefined_to_null %}
+{{argument.cpp_type}}* {{argument.name}} = nullptr;
+{{argument.cpp_type}} {{argument.name}}Value
 {%- else %}
 {{argument.cpp_type}} {{argument.name}}
 {%- endif %}{# argument.idl_type == 'EventListener' #}
 {% endmacro %}
 
 
 {######################################}
 {% macro generate_argument(method, argument, world_suffix) %}
 {% if argument.is_optional and not argument.has_default and
       not argument.is_dictionary and
@@ skipping 582 matching lines @@
                           if method.overloads else
                           method.runtime_enabled_function) %}
 v8::Local<v8::FunctionTemplate> functionTemplate = v8::FunctionTemplate::New(isolate, {{cpp_class_or_partial}}V8Internal::{{method.name}}MethodCallback, v8Undefined(), defaultSignature, {{method.number_of_required_arguments}});
 v8::Local<v8::Function> function = ->GetFunction(isolate->GetCurrentContext())).ToLocalChecked();
 v8CallOrCrash(prototypeObject->Set(isolate->GetCurrentContext(), v8AtomicString(isolate, "{{method.name}}"), function));
 {% endfilter %}{# runtime_enabled() #}
 {% endfilter %}{# exposed() #}
 {% endfor %}
 {% endif %}
 {%- endmacro %}