Allow serialization for WindowType (#762)

* Allow serialization for WindowType

* Update CHANGELOG.md

* Update CHANGELOG.md

Co-Authored-By: saschagrunert <sgrunert@suse.com>

CHANGELOG.md

@@ -1,5 +1,7 @@
 # Unreleased
 
+- Added serde serialization to `os::unix::XWindowType`.
+
 # Version 0.18.1 (2018-12-30)
 
 - On macOS, fix `Yen` (JIS) so applications receive the event.

src/platform/linux/x11/util/hint.rs

@@ -24,6 +24,7 @@ impl From<bool> for StateOperation {
 /// X window type. Maps directly to
 /// [`_NET_WM_WINDOW_TYPE`](https://specifications.freedesktop.org/wm-spec/wm-spec-1.5.html).
 #[derive(Debug, Copy, Clone, PartialEq, Eq, Hash)]
+#[cfg_attr(feature = "serde", derive(Serialize, Deserialize))]
 pub enum WindowType {
     /// A desktop feature. This can include a single window containing desktop icons with the same dimensions as the
     /// screen, allowing the desktop environment to have full control of the desktop, without the need for proxying