Dismiss widget picker activity on lock

See attached bug, we don't have good transition between lockscreen and
picker, so, we decided to dismiss it, given that this CUJ is less
common.

Additionally,

1. switch over to dagger dependencies instead of LauncherAppState
2. Remove unused flags for show_wallpaper / show_when_unlocked

Bug: 405068076
Flag: EXEMPT BUGFIX
Test: Manual (see demo in comments)
Change-Id: I8d0d5ebdbcca806e7fa24c57f80f1cad518bd035
1 file changed