tests/test-execute-bit.t

check-code: drop the camelcase checks

Fro about 2 years we have been using CamelCase is class names. That rules gets
in the way of assigning class or exception in compatibility layers.

I think it is safe to drop it now that we started using CamelCase for some case.

My motivation for this is the need to assign `FileNotFoundError` in `pycompat`.

Differential Revision: https://phab.mercurial-scm.org/D11309

#require execbit

  $ hg init
  $ echo a > a
  $ hg ci -Am'not executable'
  adding a

  $ chmod +x a
  $ hg ci -m'executable'
  $ hg id
  79abf14474dc tip

Make sure we notice the change of mode if the cached size == -1:

  $ hg rm a
  $ hg revert -r 0 a
  $ hg debugstate
  n   0         -1 unset               a
  $ hg status
  M a

  $ hg up 0
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
  $ hg id
  d69afc33ff8a
  $ test -x a && echo executable -- bad || echo not executable -- good
  not executable -- good