Fix jank in no favorites screen when showing/hiding dialpad DO NOT MERGE

Reintroduce a spacer view (under the no favorites view) that is
the same height as the search box + its margins, so that
the no favorites view does not shift when the dialpad is shown/hidden

Bug: 13341743
Change-Id: I00171b5fd546e30394c95d31976483d124f75f3b
(cherry picked from commit b0d197653fcdd2526ba9b85d613e4968ebbef2ab)