message: Remove code for setting _NET_WM_PID
  This code is no longer necessary since winit now does this for us.
diff: @@ -175,8 +175,6 @@ impl Window {
  is_focused: false,
  };
  - window.run_os_extensions();
  -
  Ok(window)
  }
  @@ -411,64 +409,6 @@ impl Window {
  }
  }
  -pub trait OsExtensions {
  - fn run_os_extensions(&self) {}
  -}
  -
  -#[cfg(any(target_os = "macos", windows))]
  -impl OsExtensions for Window {}
  -
  -#[cfg(not(any(target_os = "macos", windows)))]
  -impl OsExtensions for Window {
  - fn run_os_extensions(&self) {
  - use libc::getpid;
  - use std::ffi::CStr;
  - use std::ptr;
  - use x11_dl::xlib::{self, PropModeReplace, XA_CARDINAL};
  -
  - let xlib_display = self.window().get_xlib_display();
  - let xlib_window = self.window().get_xlib_window();
  -
  - if let (Some(xlib_window), Some(xlib_display)) = (xlib_window, xlib_display) {
  - let xlib = xlib::Xlib::open().expect("get xlib");
  -
  - // Set _NET_WM_PID to process pid
  - unsafe {
  - let _net_wm_pid = CStr::from_ptr(b"_NET_WM_PID\0".as_ptr() as *const _);
  - let atom = (xlib.XInternAtom)(xlib_display as *mut _, _net_wm_pid.as_ptr(), 0);
  - let pid = getpid();
  -
  - (xlib.XChangeProperty)(
  - xlib_display as _,
  - xlib_window as _,
  - atom,
  - XA_CARDINAL,
  - 32,
  - PropModeReplace,
  - &pid as *const i32 as *const u8,
  - 1,
  - );
  - }
  - // Although this call doesn't actually pass any data, it does cause
  - // WM_CLIENT_MACHINE to be set. WM_CLIENT_MACHINE MUST be set if _NET_WM_PID is set
  - // (which we do above).
  - unsafe {
  - (xlib.XSetWMProperties)(
  - xlib_display as _,
  - xlib_window as _,
  - ptr::null_mut(),
  - ptr::null_mut(),
  - ptr::null_mut(),
  - 0,
  - ptr::null_mut(),
  - ptr::null_mut(),
  - ptr::null_mut(),
  - );
  - }
  - }
  - }
  -}
  -
  impl Proxy {
  /// Wakes up the event loop of the window
  ///
  