(quail-simple-translation-keymap, quail-conversion-keymap):
Make the default binding with define-key.
Handle meta-prefix-char the way isearch does.
(quail-translation-keymap): Likewise.
(quail-execute-non-quail-command): Handle the key sequence as the
same way as universal-argument-other-key.
(quail-make-guidance-frame): Don't dedicate the guidance buffer window.
(quail-show-guidance-buf): Likewise.
(quail-hide-guidance-buf): Delete code to turn off window dedication.