publishing: use new helper method

publishing: add helper method to localrepo

revset: make use of natively-computed set for 'draft()' and 'secret()' If the computation of a set for each phase (done in C) is available, we use it directly instead of applying a simple filter. This give a massive speed-up in the vast majority of cases. On my mercurial repo with about 15000 out of 40000 draft changesets: revset: draft() plain min first last 0) 0.011201 0.019950 0.009844 0.000074 1) 0.000284 2% 0.000312 1% 0.000314 3% 0.000315 x4.3 Bad performance for "last" come from the handling of the 15000 elements set (memory allocation, filtering hidden changesets (99% of it) etc. compared to applying the filter only on a handfuld of revisions (the first draft changesets being close of tip). This is not seen as an issue since: * Timing is still pretty good and in line with all the other one, * Current user of Vanilla Mercurial will not have 1/3 of their repo draft, This bad effect disappears when phase's set is smaller. (about 200 secrets): revset: secret() plain min first last 0) 0.011181 0.022228 0.010851 0.000452 1) 0.000058 0% 0.000084 0% 0.000087 0% 0.000087 19%

revset: refactor the non-public phase code Code for draft and secret are the same. We'll make it more complex to take advantages of the set recomputed in C, so we first refactor the code to only have one place to update (and make sure all behave properly). We do not refactor the 'public()' code because it does not have a natively computed set.