Add per-buffer perfetto trace points for SurfaceFlinger frame events

In order to track how buffers move through the system, we add per-buffer perfetto trace points for SurfaceFlinger.
The majority of these were already tracked through TimeStats, so the new tracing was built on top of TimeStats.

Test: atest libsurfaceflinger_unittest

Run trace with:
{ adb shell perfetto   -c - --txt   -o /data/misc/perfetto-traces/trace <<EOF
buffers: {
    size_kb: 1280
}
data_sources: {
    config {
        name: "android.surfaceflinger.timestats"
    }
}
duration_ms: 3000
EOF
} && adb pull /data/misc/perfetto-traces/trace ~/Desktop/trace

Change-Id: Ifb38c64a9966fece735f0ad72438c7c9c5e07baa