dirstate: test normalize is truthy instead of using a no-op lambda
hg perfstatus -u on a working directory with 170,000 files, without this
change:
! wall 1.869404 comb 1.850000 user 1.170000 sys 0.680000 (best of 6)
With this change:
! wall 1.839561 comb 1.830000 user 1.120000 sys 0.710000 (best of 6)
$ rm -rf a
$ hg init a
$ cd a
$ echo a > a
$ hg ci -Am0
adding a
$ hg tag t1 # 1
$ hg tag --remove t1 # 2
$ hg co 1
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ hg tag -f -r0 t1
$ hg tags
tip 3:a49829c4fc11
t1 0:f7b1eb17ad24
$ cd ..