cmdutil: stop tryimportone from using dirstateguard (BC)
There is no user of 'cmdutil.tryimportone()' other than
'commands.import_()', which can restore dirstate at failure of
applying patches by transaction or dirstateguard.
Therefore, it is reasonable to stop 'tryimportone()' from using
redundant 'dirstateguard', even though it changes behavior of
'tryimportone()'.
After this patch, 3rd party extensions should use 'dirstateguard' or
so explicitly, if they want to restore dirstate at failure of
importing a patch.
test --time
$ hg --time help -q help 2>&1 | grep time > /dev/null
$ hg init a
$ cd a
#if lsprof
test --profile
$ hg --profile st 2>../out
$ grep CallCount ../out > /dev/null || cat ../out
$ hg --profile --config profiling.output=../out st
$ grep CallCount ../out > /dev/null || cat ../out
$ hg --profile --config profiling.output=blackbox --config extensions.blackbox= st
$ grep CallCount .hg/blackbox.log > /dev/null || cat .hg/blackbox.log
$ hg --profile --config profiling.format=text st 2>../out
$ grep CallCount ../out > /dev/null || cat ../out
$ echo "[profiling]" >> $HGRCPATH
$ echo "format=kcachegrind" >> $HGRCPATH
$ hg --profile st 2>../out
$ grep 'events: Ticks' ../out > /dev/null || cat ../out
$ hg --profile --config profiling.output=../out st
$ grep 'events: Ticks' ../out > /dev/null || cat ../out
#endif
$ cd ..