Implement new search bar style for new landing page design

The visual is customize theme on toolbar to make it looks like search
view. Only landing page showing as search view style, others
(Image, Video, Download...) showing as legacy toolbar.

Bug: 111914879
Bug: 116186158
Test: atest DocumentsUITests
Change-Id: I025852cf23913435241ca0a8df602f77176862cb