Perf tweaks -Consolidate some KeyguardTransition collects

Minor but consistent benefit in combining 3 transition collects
into one large one with the exact same logic.

Also, make sure bouncer collection for animations happens on the
main thread

Also, remove a couple dependencies on direct `transitions`

Bug: 402243753
Test: manual - analyze perfetto KTF
Flag: EXEMPT performance fix
Change-Id: Icd77abcbc632a31292510d46b8b6024812a2f156