Relayout the launcher image search section.

As the new layout spec is out for launcher image search, this cl
updates the layout according to the spec.
Spec: crbug/1352636#c14

Bug: 1352636
Change-Id: I2cd2bff62f8cd4441747d82f2cd9e493e2a57e83
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/4560244


Commit-Queue: Wen-Chien Wang <wcwang@chromium.org>
Reviewed-by: Toni Barzic <tbarzic@chromium.org>
Cr-Commit-Position: refs/heads/main@{#1161975}