assistant: clean up code 16 of N

* clean up feedback integration

Bug: 388361414
Change-Id: I413a9f2e5c4da53a9a73d5c56433ddf31e296340
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/6944685
Reviewed-by: Matthew Denton <mpdenton@chromium.org>
Reviewed-by: Xiangdong Kong <xiangdongkong@google.com>
Commit-Queue: Xiaohui Chen <xiaohuic@chromium.org>
Cr-Commit-Position: refs/heads/main@{#1516412}
NOKEYCHECK=True
GitOrigin-RevId: 27cfd43565db5914b392c5b135641d38b60a26f8