tests/test-confused-revert.t

phases: invalidate the phases set less often on retract boundary

We already have the information to update the phase set, so we do so directly
instead of invalidating the cache.

This show a sizeable speedup in our `perf::unbundle` benchmark on the
many-draft mozilla-try repository.

### data-env-vars.name            = mozilla-try-2023-03-22-zstd-sparse-revlog
  # benchmark.name                = hg.perf.perf-unbundle
  # bin-env-vars.hg.flavor        = no-rust
  # bin-env-vars.hg.py-re2-module = default
  # benchmark.variants.issue6528  = disabled

  # benchmark.variants.revs = last-10
before: 2.055259 seconds
after:  1.887064 seconds (-8.18%)
  # benchmark.variants.revs = last-100
before: 2.409239 seconds
after:  2.222429 seconds (-7.75%)
  # benchmark.variants.revs = last-1000
before: 3.945648 seconds
after:  3.762480 seconds (-4.64%)

  $ hg init repo
  $ cd repo
  $ echo foo > a
  $ hg add a
  $ hg commit -m "1"

  $ echo bar > b
  $ hg add b
  $ hg remove a

Should show a removed and b added:

  $ hg status
  A b
  R a

  $ hg revert --all
  forgetting b
  undeleting a

Should show b unknown and a back to normal:

  $ hg status
  ? b

  $ rm b

  $ hg co -C 0
  0 files updated, 0 files merged, 0 files removed, 0 files unresolved
  $ echo foo-a > a
  $ hg commit -m "2a"

  $ hg co -C 0
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
  $ echo foo-b > a
  $ hg commit -m "2b"
  created new head

  $ HGMERGE=true hg merge 1
  merging a
  0 files updated, 1 files merged, 0 files removed, 0 files unresolved
  (branch merge, don't forget to commit)

Should show foo-b:

  $ cat a
  foo-b

  $ echo bar > b
  $ hg add b
  $ rm a
  $ hg remove a

Should show a removed and b added:

  $ hg status
  A b
  R a

Revert should fail:

  $ hg revert
  abort: uncommitted merge with no revision specified
  (use 'hg update' or see 'hg help revert')
  [10]

Revert should be ok now:

  $ hg revert -r2 --all
  forgetting b
  undeleting a

Should show b unknown and a marked modified (merged):

  $ hg status
  M a
  ? b

Should show foo-b:

  $ cat a
  foo-b