merge with i18n

i18n-ja: synchronized with d4be314b2071

merge with stable

fileset, revset: do not use global parser object for thread safety parse() cannot be called at the same time because a parser object keeps its states. This is no problem for command-line hg client, but it would cause strange errors in multi-threaded hgweb. Creating parser object is not too expensive. original: % python -m timeit -s 'from mercurial import revset' 'revset.parse("0::tip")' 100000 loops, best of 3: 11.3 usec per loop thread-safe: % python -m timeit -s 'from mercurial import revset' 'revset.parse("0::tip")' 100000 loops, best of 3: 13.1 usec per loop

obsolete: order of magnitude speedup in _computebumpedset Reminder: a changeset is said "bumped" if it tries to obsolete a immutable changeset. The previous algorithm for computing bumped changeset was: 1) Get all public changesets 2) Find all they successors 3) Search for stuff that are eligible for being "bumped" (mutable and non obsolete) The entry size of this algorithm is `O(len(public))` which is mostly the same as `O(len(repo))`. Even this this approach mean fewer obsolescence marker are traveled, this is not very scalable. The new algorithm is: 1) For each potential bumped changesets (non obsolete mutable) 2) iterate over precursors 3) if a precursors is public. changeset is bumped We travel more obsolescence marker, but the entry size is much smaller since the amount of potential bumped should remains mostly stable with time `O(1)`. On some confidential gigantic repo this move bumped computation from 15.19s to 0.46s (×33 speedup…). On "smaller" repo (mercurial, cubicweb's review) no significant gain were seen. The additional traversal of obsolescence marker is probably probably counter balance the advantage of it. Other optimisation could be done in the future (eg: sharing precursors cache for divergence detection)

obsolete: add an allprecursors method mirroring allsuccessors one. Detection of bumped changeset should use `allprecursors(<mutable>)` instead or `allsuccessors(<immutable>)` so we need the all precursors function to exists.

perf: fix perfvolatilesets The repoview's `filteredrevs` has been renamed to `filterrevs` at some point. perf was never informed.

obsolete: improve allsuccessors doc string The fact original nodes are also yield is not obvious. We update the docstring to highlight it.

obsolete: fix bad comment We cannot afford such extra "with" they are far too pricy.

util: remove unused realpath (issue4063) util.realpath was in use for only 5 days from dbdb777502dc until it was backed out in c519cd8f0169 because it caused issue3077 and issue3071.