Fix documentation about button name

review3011004
(transplanted from 97ae3a1a8a01e1272b91bc0457f3d71bbc9f057c)

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extra : transplant_source : %97%AE%3A%1A%8A%01%E1%27%2B%91%BC%04W%F3%D7%1B%BC%9F%05%7C