[ticket/10531] Disallow deleting of the last style

Regression from PHPBB3-9675 commit 0e02f5cb0b7f615f1eadd6606a89bfd1b28f0d0d

PHPBB3-9675
PHPBB3-10531
Merge remote-tracking branch 'nickvergessen/ticket/revert/8996' into prep-release-3.0.10

* nickvergessen/ticket/revert/8996:
  [ticket/8996] Revert initial fix to keep old behaviour on empty selection Part2
  [ticket/8996] Revert initial fix to keep old behaviour on empty selection
Merge branch 'prep-release-3.0.10' into develop-olympus

* prep-release-3.0.10:
  [ticket/8996] Revert initial fix to keep old behaviour on empty selection Part2
  [ticket/8996] Revert initial fix to keep old behaviour on empty selection
Merge remote-tracking branch 'nickvergessen/ticket/10531' into prep-release-3.0.10

* nickvergessen/ticket/10531:
  [ticket/10531] Disallow deleting of the last style
Merge branch 'prep-release-3.0.10' into develop-olympus

* prep-release-3.0.10:
  [ticket/10531] Disallow deleting of the last style
Merge remote-tracking branch 'nickvergessen/ticket/10504' into prep-release-3.0.10

* nickvergessen/ticket/10504:
  [ticket/10504] Revert the changes for widescreen optimisation PHPBB3-6632
  [ticket/10504] Revert the changes for widescreen optimisation PHPBB3-10408
  [ticket/10504] Revert the changes for widescreen optimisation PHPBB3-10485
Merge branch 'prep-release-3.0.10' into develop-olympus

* prep-release-3.0.10:
  [ticket/10504] Revert the changes for widescreen optimisation PHPBB3-6632
  [ticket/10504] Revert the changes for widescreen optimisation PHPBB3-10408
  [ticket/10504] Revert the changes for widescreen optimisation PHPBB3-10485
[prep-release-3.0.10] Update Changelog for 3.0.10-RC3 release.
Merge branch 'prep-release-3.0.10' into develop-olympus

* prep-release-3.0.10:
  [prep-release-3.0.10] Update Changelog for 3.0.10-RC3 release.
[ticket/10538] Call htmlspecialchars_decode() on Jabber and SMTP passwords.

PHPBB3-10538
Merge remote-tracking branch 'cyberalien/ticket/10399' into develop-olympus

* cyberalien/ticket/10399:
  [ticket/10399] Correctly encoding template component urls (3.0)
  [ticket/10399] Correctly encoding template component urls (3.0)
[ticket/10546] Add missing argument to adm_back_link in acp_captcha.

PHPBB3-10546
[ticket/9681] Add password length to security settings

PHPBB3-9681
[ticket/7432] Explain what users are inactive in more detail.

PHPBB3-7432
Merge remote-tracking branch 'p/ticket/10546' into develop-olympus

* p/ticket/10546:
  [ticket/10546] Add missing argument to adm_back_link in acp_captcha.
Merge remote-tracking branch 'cyberalien/ticket/10507' into develop-olympus

* cyberalien/ticket/10507:
  [ticket/10507] DBAL unit test
  [ticket/10507] Sort styles in acp
[ticket/9079] Display backtrace on all E_USER_ERROR errors, not only SQL errors

PHPBB3-9079
[ticket/9079] Always log backtrace to error log when logging errors.

PHPBB3-9079
[ticket/10542] Remove class="postlink" in subsilver2 faq_body.html

class="postlink" is not defined in stylesheet.css so remove it from
styles/subsilver2/template/faq_body.html

PHPBB3-10542
Merge remote-tracking branch 'Dickyf/ticket/10542' into develop-olympus

* Dickyf/ticket/10542:
  [ticket/10542] Remove class="postlink" in subsilver2 faq_body.html