Fix scrolling position not kept in Trusted Credentials

For example when changing display states.

Save view states to solve this issue.
 - Save current tab. (System / User)
 - Save group expanded state. (Personal / Work)
 - Save scrolling position of each group.

Also updated to ViewPager2 and updated the styles.

Bug: 204839552
Test: manual
Change-Id: Ibeda50b50e7dfd2ba071b75fe2aa88ef560f4c88
4 files changed