Fix find button in search window

It should use the text filled in the search entry.
And it should not close the window if nothing is found.

review3101003
(transplanted from 8b22f7366f7caeb7ecbe86c28b8b4f8f3bf32627)

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extra : transplant_source : %8B%22%F76o%7C%AE%B7%EC%BE%86%C2%8B%8BO%8F%3B%F3%26%27