Treat null dictionary members as missing per WebIDL

third_party/WebKit/Source/bindings/templates/dictionary_v8.cpp

 {% filter format_blink_cpp_source_code %}
 
 {% from 'utilities.cpp' import declare_enum_validation_variable %}
 {% include 'copyright_block.txt' %}
 #include "{{v8_original_class}}.h"
 
 {% for filename in cpp_includes if filename != '%s.h' % v8_class %}
 #include "{{filename}}"
 {% endfor %}
 
@@ skipping 33 matching lines @@
         return;
     }
     {% endif %}
     {% for member in members %}
     {% filter runtime_enabled(member.runtime_enabled_function) %}
     v8::Local<v8::Value> {{member.name}}Value;
     if (!v8Object->Get(isolate->GetCurrentContext(), v8String(isolate, "{{member.name}}")).ToLocal(&{{member.name}}Value)) {
         exceptionState.rethrowV8Exception(block.Exception());
         return;
     }
-    if ({{member.name}}Value.IsEmpty() || {{member.name}}Value->IsUndefined()) {
+    if (isUndefinedOrNull({{member.name}}Value)) {
         {% if member.is_required %}
         exceptionState.throwTypeError("required member {{member.name}} is undefined.");
         return;
         {% else %}
         // Do nothing.
         {% endif %}
-    {% if member.is_nullable %}
-    } else if ({{member.name}}Value->IsNull()) {
-        impl.{{member.null_setter_name}}();
-    {% endif %}
     } else {
         {% if member.deprecate_as %}
         Deprecation::countDeprecationIfNotPrivateScript(isolate, currentExecutionContext(isolate), UseCounter::{{member.deprecate_as}});
         {% endif %}
         {{v8_value_to_local_cpp_value(member) | indent(8)}}
         {% if member.is_interface_type %}
-        if (!{{member.name}} && !{{member.name}}Value->IsNull()) {
+        if (!{{member.name}}) {
             exceptionState.throwTypeError("member {{member.name}} is not of type {{member.idl_type}}.");
             return;
         }
         {% endif %}
         {% if member.enum_values %}
         {{declare_enum_validation_variable(member.enum_values) | indent(8)}}
         if (!isValidEnum({{member.name}}, validValues, WTF_ARRAY_LENGTH(validValues), "{{member.enum_type}}", exceptionState))
             return;
         {% elif member.is_object %}
         if (!{{member.name}}.isObject()) {
@@ skipping 51 matching lines @@
 {{cpp_class}} NativeValueTraits<{{cpp_class}}>::nativeValue(v8::Isolate* isolate, v8::Local<v8::Value> value, ExceptionState& exceptionState)
 {
     {{cpp_class}} impl;
     {{v8_class}}::toImpl(isolate, value, impl, exceptionState);
     return impl;
 }
 
 } // namespace blink
 
 {% endfilter %}{# format_blink_cpp_source_code #}