[SharedArrayBuffer] Prevent SharedArrayBuffer being used in Web APIs

third_party/WebKit/Source/bindings/templates/union_container.cpp.tmpl

 {% from 'utilities.cpp.tmpl' import declare_enum_validation_variable %}
 {% from 'utilities.cpp.tmpl' import v8_value_to_local_cpp_value %}
 {#############################################################################}
 {% macro assign_and_return_if_hasinstance(member) %}
 {% if member.is_array_buffer_or_view_type %}
 if (v8Value->Is{{member.type_name}}()) {
 {% else %}
 if (V8{{member.type_name}}::hasInstance(v8Value, isolate)) {
 {% endif %}
+{% if member.is_array_buffer_view_or_typed_array %}
+  {{member.cpp_local_type}} cppValue = toNotShared<{{member.cpp_local_type}}>(isolate, v8Value, exceptionState);
+  if (exceptionState.hadException())
+    return;
+{% else %}
   {{member.cpp_local_type}} cppValue = V8{{member.type_name}}::toImpl(v8::Local<v8::Object>::Cast(v8Value));
+{% endif %}
   impl.set{{member.type_name}}(cppValue);
   return;
 }
 {% endmacro %}
 {#############################################################################}
 {% filter format_blink_cpp_source_code %}
 {% include 'copyright_block.txt' %}
 #include "{{this_include_header_name}}.h"
 
 {% for filename in cpp_includes %}
@@ skipping 186 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, UnionTypeConversionMode::NotNullable, exceptionState);
   return impl;
 }
 
 }  // namespace blink
 
 {% endfilter %}{# format_blink_cpp_source_code #}