Fix bug 5339708 - edge case in ListView focus restoration

Some apps have managed to hit this edge case in monkey runs. In
layoutChildren an attempt to findFocus() fails when items are
focusable. When ListView attempts to restore focus to this view,
bad things happen.

Change-Id: Ie8bb1bab847898e342c16fbe3ff1a6153d6f69df
1 file changed