www/qt6-webengine: Switch to bundled re2

[kai]

Summary

* Prepare the port for newer versions of devel/re2, which also require
  devel/abseil.  This combination however causes build errors [1] due
  to missing symbols:

[...]
In file included from gen/extensions/browser/browser_sources_jumbo_8.cc:6:
./../../../../../qtwebengine-everywhere-src-6.5.2/src/3rdparty/chromium/extensions/browser/api/web_request/form_data_parser.cc:429:11: error: no member named 'set' in 'absl::string_view'
  source_.set(source.data(), source.size());
  ~~~~~~~ ^
./../../../../../qtwebengine-everywhere-src-6.5.2/src/3rdparty/chromium/extensions/browser/api/web_request/form_data_parser.cc:573:11: error: no member named 'set' in 'absl::string_view'
  source_.set(source.data(), source.size());
  ~~~~~~~ ^
[...]

  Unbundling abseil and its-subcomponents via "replace_gn_files.py" didn't
  help hence switch to the bundled re2 for now to have a consistent
  combination of re2 and abseil.

* Bump PORTREVISION due dependency change.

PR: 260402 [1]
Reported by: diizzy [1]

Test Plan

• poudriere -> OK (12.4-, 13.2-RELEASE, 14.0-CURRENT@38f5cb1bfbe1 amd64 i386) [*]
• small runtime tests with deskutils/calibre, games/anki and` www/dooble` on 12.4-RELEASE amd64

Note *: for ALSA/PULSEAUDIO/SNDIO without DEBUG. With DEBUG the build fails at the moment and it's already the case with www/qt6-webengine 6.5.2_2.

Already tried:

• Tried to unbundle abseil and its sub-components via absl_base" absl_cleanup etc. with replace_gn_files.py. This revealed more GN targets, e.g. absl_tests, that need unbundling but are (still) too intertwined in the GN files and there's no directive, e.g. absl_tests to unbundle them. The GN system lacks also a directive, e.g. use_system_abseil or similar, to use .

• Used the attached patch in bug #270233 (= abseil 20230125.1), but the build fails with the same error.

I'm open for further ideas because I might also overlook something.

[tcberner]

Moin moin

I think it's fine to do this.

mfg Tobias

[diizzy]

Looks similar to what I'm seeing trying to bump re2. https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=260402
I'm fine with bundling these lips for now, I think it's worth keeping a note in the Makefile why we're bundling these libraries and/or link to this review.

[kai]

Thanks for your advice, @tcberner, @diizzy and yes, it's definitely a good idea to leave an appropriate comment in the Makefile.