tests/test-hgk.t

test-revert: put content, not keys, into 'combination'

By putting the file content rather than keys in the 'combination'
list, we restrict the knowledge of 'ctxcontent' and 'wccontent' to the
loop generating the combinations. That will make it easier to replace
the generation code.

Minimal hgk check

  $ echo "[extensions]" >> $HGRCPATH
  $ echo "hgk=" >> $HGRCPATH
  $ hg init repo
  $ cd repo
  $ echo a > a
  $ hg ci -Am adda
  adding a
  $ hg debug-cat-file commit 0
  tree a0c8bcbbb45c
  parent 000000000000
  author test 0 0
  revision 0
  branch default
  phase draft
  
  adda

  $ cd ..