Consistently apply traces as defined in #127125 for branch profile aggregation. This combines branches and fall-through records into one. With large input binaries/profiles, the speed up in aggregation time (`-time-aggr`, wall time): - perf.data, pre-BOLT input: 154.5528s -> 144.0767s - pre-aggregated data, pre-BOLT input: 15.1026s -> 9.0711s - pre-aggregated data, BOLTed input: 15.4871s -> 10.0077s Test Plan: NFC