Revert "Merge pull request #10669 from RudyLu/keyboard/swipe_hide_keyboard_2"

This reverts commit 103f3635c241e208f84b6e8d80afb23731043c09, reversing
changes made to 4be813b65ea30e3914ce732d1401385d8fb78b68.

See https://bugzilla.mozilla.org/show_bug.cgi?id=892377