metal: preserve mode across reconnects

src/ifs/wl_output.rs

@@ -96,14 +96,30 @@ pub struct PersistentOutputState {
     pub tearing_mode: Cell<&'static TearingMode>,
 }
 
-#[derive(Eq, PartialEq, Hash)]
+#[derive(Eq, PartialEq, Hash, Debug)]
 pub struct OutputId {
-    pub connector: String,
+    pub connector: Option<String>,
     pub manufacturer: String,
     pub model: String,
     pub serial_number: String,
 }
 
+impl OutputId {
+    pub fn new(
+        connector: String,
+        manufacturer: String,
+        model: String,
+        serial_number: String,
+    ) -> Self {
+        Self {
+            connector: serial_number.is_empty().then_some(connector),
+            manufacturer,
+            model,
+            serial_number,
+        }
+    }
+}
+
 impl WlOutputGlobal {
     pub fn clear(&self) {
         self.opt.clear();