tests/test-server-view.t

run-tests: fix `HGTESTEXTRAEXTENSIONS` with py3

Since `extensions` was a str and `section` bytes, it never populated anything.
If it had, it would have put bytes into the environment dictionary that is all
str.  As everything starts and ends as str, remove the incomplete attempt at
byteification.  It doesn't appear that we had any test coverage of this bit of
code, so also add a non-extension config to make sure it is filtered out
properly.

Differential Revision: https://phab.mercurial-scm.org/D9557

  $ hg init test
  $ cd test
  $ hg debugbuilddag '+2'
  $ hg phase --public 0

  $ hg serve -p $HGPORT -d --pid-file=hg.pid -E errors.log
  $ cat hg.pid >> $DAEMON_PIDS
  $ cd ..
  $ hg init test2
  $ cd test2
  $ hg incoming http://foo:xyzzy@localhost:$HGPORT/
  comparing with http://foo:***@localhost:$HGPORT/
  changeset:   0:1ea73414a91b
  user:        debugbuilddag
  date:        Thu Jan 01 00:00:00 1970 +0000
  summary:     r0
  
  changeset:   1:66f7d451a68b
  tag:         tip
  user:        debugbuilddag
  date:        Thu Jan 01 00:00:01 1970 +0000
  summary:     r1
  
  $ killdaemons.py

  $ cd ..
  $ hg -R test --config server.view=immutable serve -p $HGPORT -d --pid-file=hg.pid -E errors.log
  $ cat hg.pid >> $DAEMON_PIDS
  $ hg -R test2 incoming http://foo:xyzzy@localhost:$HGPORT/
  comparing with http://foo:***@localhost:$HGPORT/
  changeset:   0:1ea73414a91b
  tag:         tip
  user:        debugbuilddag
  date:        Thu Jan 01 00:00:00 1970 +0000
  summary:     r0
  

Check same result using `experimental.extra-filter-revs`

  $ hg -R test --config experimental.extra-filter-revs='not public()' serve -p $HGPORT1 -d --pid-file=hg2.pid -E errors.log
  $ cat hg2.pid >> $DAEMON_PIDS
  $ hg -R test2 incoming http://foo:xyzzy@localhost:$HGPORT1/
  comparing with http://foo:***@localhost:$HGPORT1/
  changeset:   0:1ea73414a91b
  tag:         tip
  user:        debugbuilddag
  date:        Thu Jan 01 00:00:00 1970 +0000
  summary:     r0
  
  $ hg -R test --config experimental.extra-filter-revs='not public()' debugupdatecache
  $ ls -1 test/.hg/cache/
  branch2-base%89c45d2fa07e
  branch2-immutable%89c45d2fa07e
  branch2-served
  branch2-served%89c45d2fa07e
  branch2-served.hidden%89c45d2fa07e
  branch2-visible%89c45d2fa07e
  branch2-visible-hidden%89c45d2fa07e
  hgtagsfnodes1
  rbc-names-v1
  rbc-revs-v1
  tags2
  tags2-served%89c45d2fa07e

cleanup

  $ cat errors.log
  $ killdaemons.py