core: don't add damage in handle_new_windows

Since commit 95a64acf5a, fill_win doesn't
set the window geometry anymore, so we can't use it in
handle_new_windows.

However, we don't need to add damage in handle_new_windows anyway,
damage will be added later when the MAPPED flag is handled.

Signed-off-by: Yuxuan Shui <yshuiv7@gmail.com>

src/picom.c

@@ -1386,7 +1386,6 @@ static void handle_new_windows(session_t *ps) {
 				// and created the damage handle. And there is no way for
 				// us to find out. So just blindly mark it damaged
 				mw->ever_damaged = true;
-				add_damage_from_win(ps, mw);
 			}
 		}
 	}