Misc bug fixes around search bar in app list UI.

- Turn off DEBUG log flag, it's spammy and is a potential PII risk.
- Save search bar expand state so it stays open during screen rotation.
- Introduce a intent extra so callers can deep link into this UI with
  search bar pre-expanded.

Fixes: 130422388
Test: robotest
Change-Id: Ib81080733707306de516c49340571c543e70874e