fix, virtual display bugs

1. Clear the map on reset.
2. Replace `containsKey` to `contains` in flutter.

Signed-off-by: fufesou <shuanglongchen@yeah.net>

src/virtual_display_manager.rs

@@ -142,6 +142,8 @@ pub fn reset_all() -> ResultType<()> {
     let mut manager = VIRTUAL_DISPLAY_MANAGER.lock().unwrap();
     if !manager.peer_index_name.is_empty() || manager.headless_index_name.is_some() {
         manager.install_update_driver()?;
+        manager.peer_index_name.clear();
+        manager.headless_index_name = None;
     }
     Ok(())
 }