Issue #1742438 by larowlan, Christian Biggins, kim.pepper, dcam, Everett Zufelt, mgifford: Fixed Vertical tabs header and container rendered even when no vertical tabs.

Issue #699604 by cam8001, nmudgal: Use file name for links to form API reference instead of full URL

Issue #171267 by tim.plunkett, chx, NROTC_Webmaster, dcam: Fixed form redirects removes get variables like sort and order.

Issue #635046 by claudiu.cristea, sun, fago: Fixed form_state_values_clean() is polluting form values.

Issue #811542 by David_Rothstein, attiks, thekevinday, effulgentsia, chx: Fixed Regression: Optional radio buttons with an empty, non-NULL default value led to an illegal choice error when none were selected.

Issue #1591726 by sun, tim.plunkett: Fixed Missing form_id, form_build_id, and form_token when using custom #parents and #tree = TRUE on $form itself.

Issue #1421410 by andypost, Niklas Fiekas: Fixed  not defined in form_pre_render_conditional_form_element().

Revert "Issue #1475666 by filijonka, Niklas Fiekas, Devin Carlson, Kevin Morse, tstoeckler: Fixed PHP error because of typo in form.inc line 3025."

This reverts commit ea8e74bb.

Issue #1475666 by filijonka, Niklas Fiekas, Devin Carlson, Kevin Morse, tstoeckler: Fixed PHP error because of typo in form.inc line 3025.

Issue #811542 by bojanz, sun, mlncn, chx, pillarsdotnet, loganfsmyth, xjm: Fixed Regression: Required radios throw illegal choice error when none selected.

Issue #381994 by xjm, good_man, elcuco, brianV, yhager: Fixed Machine-name fields are always in Latin characters, and should therefore always be LTR.

Issue #866292 by marcingy, ygerasimov, quicksketch, attiks, furamag: Fixed '0' not displayed as checkbox / radios options (nor as any element #title).

- Patch #1229868 by nicl, DjebbZ: hook_form_BASE_FORM_ID_alter(), hook_form_alter(), and hook_form_FORM_ID_alter() doc inconsistent.

Issue #570314 follow-up by jhodgdon, Mac_Weber: Fixed form_set_value() documentation needs more detail.

- Patch #240828 by sun, xjm, David_Rothstein, yoroy: 'This form is outdated. Reload the page and try again' is incorrect and confuses users.

Issue #1118016 by dereine, pwolanin: Fixed conditional visibility of a managed_file() using #states attribute does not work.

Issue #1174444 by Boobaa, xjm, Dave Reid: Make the _element_validate_()* functions in field.module available for all contrib modules to use.

Issue #1174444 by Boobaa, xjm, Dave Reid: Make the _element_validate_()* functions in field.module available for all contrib modules to use.