largefiles: backout f72d73937853 - linear updates handle m -> a differently
f72d73937853 introduced a significant performance regression: All largefiles
were marked 'normallookup' by linear (or noop) updates and had to be rehashed
by the next command.
The previous change introduced a different solution to the problem f72d73937853
solved and we can thus back it out again.
to build a new macosx binary package:
install macpython from http://www.python.org/download/mac
install py2app from http://pythonmac.org/packages/
make sure /usr/local/bin is in your path
run bdist_mpkg in top-level hg directory
find packaged stuff in dist directory