This is similar to the change we did for the v3 format in 6e4c8366c5ce.

The benchmark bellow show this gives us a notable gains, especially on larger
repositories.

### benchmark.name                = hg.perf.stream-locked-section
  # benchmark.name                = hg.perf.stream-locked-section
  # bin-env-vars.hg.flavor        = default
  # bin-env-vars.hg.py-re2-module = default
  # benchmark.variants.version    = v2
 ## data-env-vars.name            = pypy-2018-08-01-zstd-sparse-revlog
5e931bf8707c: 0.503820  ~~~~~
1106d1bf695e: 0.470078   (-6.70%, -0.03)
 ## data-env-vars.name            = pypy-2024-03-22-zstd-sparse-revlog
5e931bf8707c: 0.535756  ~~~~~
1106d1bf695e: 0.490249   (-8.49%, -0.05)
 ## data-env-vars.name            = heptapod-public-2024-03-25-zstd-sparse-revlog
5e931bf8707c: 1.327041  ~~~~~
1106d1bf695e: 1.174636  (-11.48%, -0.15)
 ## data-env-vars.name            = netbeans-2018-08-01-zstd-sparse-revlog
5e931bf8707c: 2.439158  ~~~~~
1106d1bf695e: 2.220515   (-8.96%, -0.22)
 ## data-env-vars.name            = netbeans-2019-11-07-zstd-sparse-revlog
5e931bf8707c: 2.630794  ~~~~~
1106d1bf695e: 2.261473  (-14.04%, -0.37)
 ## data-env-vars.name            = mozilla-central-2018-08-01-zstd-sparse-revlog
5e931bf8707c: 5.769002  ~~~~~
1106d1bf695e: 5.062000  (-12.26%, -0.71)
 ## data-env-vars.name            = mozilla-try-2019-02-18-zstd-sparse-revlog
5e931bf8707c: 13.351750  ~~~~~
1106d1bf695e: 12.346655   (-7.53%, -1.01)
 ## data-env-vars.name            = mozilla-central-2024-03-22-zstd-sparse-revlog
5e931bf8707c: 10.772939  ~~~~~
1106d1bf695e: 9.495407  (-11.86%, -1.28)
 ## data-env-vars.name            = mozilla-unified-2024-03-22-zstd-sparse-revlog
5e931bf8707c: 10.864297  ~~~~~
1106d1bf695e: 9.475597  (-12.78%, -1.39)
 ## data-env-vars.name            = mozilla-try-2023-03-22-zstd-sparse-revlog
5e931bf8707c: 17.448335  ~~~~~
1106d1bf695e: 16.027474   (-8.14%, -1.42)