[TS] Allow access to enum variant classes in internal files

This allows our own code to do things like
`(a instanceof Option_ThingZ_Some)`, though it doesn't impact the
public API.

Author: TheBlueMatt

typescript_strings.py

@@ -1464,7 +1464,7 @@ def map_complex_enum(self, struct_name, variant_list, camel_to_snake, enum_doc_c
                 out_java += self.fn_call_body(fn_name, field_map.c_ty, field_map.java_ty, "ptr: bigint", "ptr")
         out_java_enum += java_hu_class
         self.struct_file_suffixes[java_hu_type] = java_hu_subclasses
-        self.obj_defined([java_hu_type], "structs")
+        self.obj_defined([java_hu_type] + [java_hu_type + "_" + var.var_name for var in variant_list], "structs")
         return (out_java, out_java_enum, out_c)
 
     def map_opaque_struct(self, struct_name, struct_doc_comment):