Data control: Resend selection when not following through with request

Normal event flow is from a client view is -> wlr_data_control_device.set_selection wlr_data_control_device.selection or wlr_data_control_source.cancelled wlr_data_control_device.selection However when the race mentioned in the comment happens the client sees -> wlr_data_control_device.set_selection wlr_data_control_device.selection wlr_data_control_source_cancelled Which can confuse client state thinking the clipboard didn't change as it associates the selection event with its own request. Resend the selection event in this case to tell the client the correct selection. BUG:464509 FIXED-IN:5.27

(cherry picked from commit d6b75907)