Ensure that Priority's Default impl always uses the correct default value

Author: sdroege

src/source.rs

@@ -262,7 +262,7 @@ pub fn source_remove(source_id: SourceId) {
 
 /// The priority of sources
 ///
-#[derive(Clone, Copy, Debug, Default, Eq, PartialEq)]
+#[derive(Clone, Copy, Debug, Eq, PartialEq)]
 pub struct Priority(i32);
 
 impl ToGlib for Priority {
@@ -281,6 +281,12 @@ impl FromGlib<i32> for Priority {
     }
 }
 
+impl Default for Priority {
+    fn default() -> Priority {
+        PRIORITY_DEFAULT
+    }
+}
+
 pub const PRIORITY_HIGH: Priority = Priority(glib_ffi::G_PRIORITY_HIGH);
 pub const PRIORITY_DEFAULT: Priority = Priority(glib_ffi::G_PRIORITY_DEFAULT);
 pub const PRIORITY_HIGH_IDLE: Priority = Priority(glib_ffi::G_PRIORITY_HIGH_IDLE);