repoview: make propertycache.setcache compatible with repoview Propertycache used standard attribute assignment. In the repoview case, this assignment was forwarded to the unfiltered repo. This result in: (1) unfiltered repo got a potentially wrong cache value, (2) repoview never reused the cached value. This patch replaces the standard attribute assignment by an assignment to `objc.__dict__` which will bypass the `repoview.__setattr__`. This will not affects other `propertycache` users and it is actually closer to the semantic we need. The interaction of `propertycache` and `repoview` are now tested in a python test file.

  $ "$TESTDIR/hghave" unix-permissions || exit 80

  $ hg init a
  $ echo a > a/a
  $ hg -R a ci -A -m a
  adding a

  $ hg clone a b
  updating to branch default
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved

  $ echo b > b/b
  $ hg -R b ci -A -m b
  adding b

  $ chmod 100 a/.hg/store

  $ hg -R b push a
  pushing to a
  abort: could not lock repository a: Permission denied
  [255]

  $ chmod 700 a/.hg/store