servo panic on 404 on windows 10 x64

[yoava333]

I'm using ea97c89 on windows 10 x64 (build 10586.104)

$ ./mach run -r "github.com"
thread 'file_loader' panicked at 'called `Result::unwrap()` on an `Err` value: ()', ../src/libcore\result.rs:746
stack backtrace:
   0:          0x1f5255a - std::panicking::default_hook::_$u7b$$u7b$closure$u7d$$u7d$::hff309ab1d83ffd90
   1:          0x1f51a7e - std::panicking::default_hook::h08ad3bb09872855b
   2:          0x1f14383 - std::sys_common::unwind::begin_unwind_inner::h406d5f1a330b854b
   3:          0x1f15f1b - std::sys_common::unwind::begin_unwind_fmt::h57ea3fbee1a40196
   4:          0x1f44bab - rust_begin_unwind
   5:          0x1f66ca5 - core::panicking::panic_fmt::ha6b3c19493c123b3
   6:           0x65c667 - core::result::unwrap_failed::hc5796116158c407f
   7:           0x6e452f - net::about_loader::factory::h2dd95ebc77145e52
   8:           0x7ade91 - net::file_loader::factory::_$u7b$$u7b$closure$u7d$$u7d$::h510cd542afffd2e1
   9:           0x7b02e4 - std::sys_common::unwind::try::try_fn::h891fad2e831a5294
  10:          0x1f44ada - std::sys_common::unwind::inner_try::h4e97625a08807651
  11:           0x7b06c2 - _<F as std..boxed..FnBox<A>>::call_box::h0a7803486bea5924
  12:          0x1f4fa89 - std::sys::thread::Thread::new::thread_start::h200b9f4ad995aaf5
  13:     0x7ffd86108101 - mz_zip_writer_add_to_central_dir.constprop.15

[jdm]

Specifically, this is the file loader redirecting to about:not-found, and that code is panicking when calling load_data.url = Url::from_file_path(&*path).unwrap();.

[yoava333]

I have fixed this issue in a PR for rust-url servo/rust-url#185