(offset_is_register): New variable
(forwarding_offset): Use apply_args_register_offset to get
register offset.
(encode_method_def, encode_method_prototype): Prepend argument
offset by '+' if passed in register.
(apply_args_register_offset): Added declaration.
(generate_method_descriptors, generate_ivar_lists,
generate_dispatch_tables): Reorganized use of constructors.
(build_descriptor_table_initializer, build_ivar_list_initializer,
build_dispatch_table_initializer): Removed argument `int *size'.