Reland "SF: Encapsulate frame targeting"

Introduce FrameTargeter to isolate a display's per-frame metrics around
past/upcoming deadline targets. The Scheduler updates the FrameTargeter
on frame begin/end, whereas ICompositor (concretely SurfaceFlinger) has
read-only access via the FrameTarget interface.

For now, only instantiate the pacesetter's FrameTargeter.

The reverted Idf9f43b37f3479c94a478d154eaa46f43e0c6c9d had an incorrect
functional change that adjusted `earliestPresentTime` based on the past
VSYNC, which differs from the previous frame's VSYNC when targeting two
VSYNCs ahead. This CL restores the `earliestPresentTime` to be relative
to the previous frame.

Bug: 262269033
Bug: 241285475
Bug: 241285191
Test: Perfetto
Test: dumpsys SurfaceFlinger --scheduler
Test: atest libscheduler_test:FrameTargeterTest
Test: systemui-bubble-1-jank-suite on raven-userdebug
Change-Id: I584e299e8af55baae1125f45fd47b13f705a268c