www: do not obfuscate addresses in URLs

As they are likely Message-IDs.   If an email address ends up in
a URL, then it's likely public, so there's even less reason to
obfuscate that particular address.

[km: add xt/perf-obfuscate.t]
[ew: modernize perf test (5.10.1), use diag instead of print]

This version of the patch avoids the massive slowdown noted by Kyle in
<https://public-inbox.org/meta/87wnt9or6t.fsf@kyleam.com/>.
Performance remains roughly the same, if not slightly faster
(which may be due to me testing this on a busy server).  Results
from xt/perf-obfuscate.t against 6078 messages on a local mirror
of <https://public-inbox.org/meta/>:

	before: 6.67 usr + 0.04 sys = 6.71 CPU
	 after: 6.64 usr + 0.04 sys = 6.68 CPU

Reported-by: Kyle Meyer <kyle@kyleam.com>
Helped-by: Kyle Meyer <kyle@kyleam.com>
Link: https://public-inbox.org/meta/87a6q8p5qa.fsf@kyleam.com/

1 files changed, 1 insertions, 0 deletions

diff --git a/MANIFEST b/MANIFEST
index b663c2a2..12247ad2 100644
--- a/MANIFEST
+++ b/MANIFEST
@@ -504,6 +504,7 @@ xt/net_writer-imap.t
 xt/nntpd-validate.t
 xt/perf-msgview.t
 xt/perf-nntpd.t
+xt/perf-obfuscate.t
 xt/perf-threading.t
 xt/solver.t
 xt/stress-sharedkv.t