Constant clipboard_x11::ALLOW_ASYNC_KEYBOARD

pub const ALLOW_ASYNC_KEYBOARD: u32 = 3; // 3u32

For AsyncKeyboard, if the keyboard is frozen by the client, keyboard event processing continues normally. If the keyboard is frozen twice by the client on behalf of two separate grabs, AsyncKeyboard thaws for both. AsyncKeyboard has no effect if the keyboard is not frozen by the client, but the keyboard need not be grabbed by the client.