profiling: add statprof support for Chrome trace viewer rendering
We synthesize function call begin/end events from snapshots, and
try (configurably) to eliminate "noisy" stack frames.
Example invocation:
hg --config profiling.output=$HOME/Desktop/clone.json \
--config profiling.statformat=chrome \
--profile clone https://www.mercurial-scm.org/repo/hg
https://bz.mercurial-scm.org/1089
$ hg init
$ mkdir a
$ echo a > a/b
$ hg ci -Am m
adding a/b
$ hg rm a
removing a/b (glob)
$ hg ci -m m a
$ mkdir a b
$ echo a > a/b
$ hg ci -Am m
adding a/b
$ hg rm a
removing a/b (glob)
$ cd b
Relative delete:
$ hg ci -m m ../a
$ cd ..