Fix focus transition when the direction is backward.

Currently, when SearchView is focused, the focus is moved to the
internal view. This blocks users to move the focus back to the previous
view by Shift + Tab.
Send focus to the previous view instead of the internal view when the
direction is backward.

Bug: 191405735
Test: atest SearchViewTest SearchView_CursorTest
Change-Id: I668ce13472b80da2e57e84fac4966294d7848170