LineageParts: Fix animation for search results

* Current implementation of the highlight when clicking a search result
  pointing to a LineageParts setting isn't working at all
* Kang the widget from settings and adapt it accordingly

Test:
Before:
Search for any AOSP setting (not title)
Click it -> it highlights (by flashing)
Search for any setting from LineageOS, e.g. "arrow keys"
Click it -> won't highlight

After:
Both results behave the same

Change-Id: Ib7e5edc3c62084a8217aa3270cd71cc57389f8a1