view CONTRIBUTING @ 35736:29f57ce416ed

localrepo: micro-optimize __len__() to bypass repoview

Since len(changelog) isn't overridden, we don't have to validate a cache of
unfiltered changelog.

  $ python -m timeit -n 10000 \
           -s 'from mercurial import hg, ui; repo = hg.repository(ui.ui());' \
           'len(repo)'
  orig) 10000 loops, best of 3: 32.1 usec per loop
  new)  10000 loops, best of 3: 1.79 usec per loop

Spotted by Jordi Gutiérrez Hermoso.

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