Panic in gtksink example

Created by: thatcodeguy

$ RUST_BACKTRACE=1 ./gtksink.exe
thread 'main' panicked at 'called `Option::unwrap()` on a `None` value', src\libcore\option.rs:335:20
stack backtrace:
   0: std::sys_common::backtrace::_print
   1: std::panicking::default_hook::{{closure}}
   2: std::panicking::default_hook
   3: std::panicking::rust_panic_with_hook
   4: std::panicking::begin_panic
   5: std::panicking::begin_panic_fmt
   6: rust_begin_unwind
   7: core::panicking::panic_fmt
   8: core::panicking::panic
   9: <core::option::Option<T>>::unwrap
             at C:\projects\rust\src\libcore/macros.rs:22
  10: gtksink::create_ui
             at src\bin/gtksink.rs:29
  11: core::ops::function::Fn::call
             at C:\projects\rust\src\libcore\ops/function.rs:48
  12: gio::auto::application::activate_trampoline
             at C:\Users\xx\.cargo\git\checkouts\gio-a4b825b310a073b9\4c69584\src\auto/application.rs:491
  13: unit_addrs_search
  14: unit_addrs_search
  15: unit_addrs_search
  16: unit_addrs_search
  17: unit_addrs_search
  18: unit_addrs_search
  19: <O as gio::auto::application::ApplicationExt>::run
             at C:\Users\xx\.cargo\git\checkouts\gio-a4b825b310a073b9\4c69584\src\auto/application.rs:297
  20: gtksink::main
             at src\bin/gtksink.rs:123
  21: _rust_maybe_catch_panic
  22: std::rt::lang_start
  23: main
  24: _tmainCRTStartup
  25: mainCRTStartup
  26: unit_addrs_search

Am I missing something obvious here?

nightly-x86_64-pc-windows-gnu is the target.