Issue #2082117 by alexpott, xjm, tim.plunkett, heyrocker, beejeebus, sun: Fixed Install default config only when the owner and provider modules are both enabled.

Revert "Issue #2082117 by alexpott: Fixed Install default config only when the owner and provider modules are both enabled."

This reverts commit 4c304cb8.

Issue #2082117 by alexpott: Fixed Install default config only when the owner and provider modules are both enabled.

Issue #2058761 by thedavidmeister: PHP notice when #attributes is not set with #theme_wrappers() 'container'.

Issue #2061835 by thedavidmeister, Cottser: Fixed theme() doesn't enforce that what it returns is a string or FALSE.

Issue #2032535 by dawehner, katbailey, pwolanin, Crell: Resolve 'title/title callback' by adding a _title propery on the route and allow a title be part of the render array.

Issue #2011578 by mortendk, tlattimore, Cottser, soulston: Markup for Stark's page.html.twig + maintenance-page.html.twig.

Issue #2010126 follow-up by Eric_A: Replace theme() with drupal_render() in image module for theme_image_formatter().

Issue #2045923 by drupalrv, tim.plunkett: Replace all module_invoke_all() deprecated function calls in procedural code.

Issue #2031319 by jlindsey15, pplantinga, thedavidmeister, Kingdutch, Kiphaas7: Document that theme() should really be called via drupal_render().

Issue #1843650 by Mark Carver, jenlampton, Cottser: Remove the process layer (hook_process() and hook_process_HOOK).

Issue #1589968 by cr0ss, Cottser, Pancho, DarthDrupal, Mark Carver: Move Title from process to preprocess, remove template_process_page().

Issue #2008270 by mcjim, typhonius: Remove drupal_add_css() from _drupal_maintenance_theme() — use #attached.

Issue #1843668 by Cottser, bdragon, joelpittet, gloob: Move building of breadcrumb render array from template_process_page() to template_preprocess_page().

Issue #2004286 by joelpittet, jenlampton, Cottser, LinL: Defer calls to drupal_get_()* functions until printed inside a template by adding a RenderWrapper class.

Issue #2030457 by Mark Carver, Cottser: Fixed Warning: Missing argument 3 for template_preprocess() for theme functions overridden by templates.

Issue #2031305 by jenlampton, thedavidmeister: Remove theme_more_help_link() and replace with a #type link render array.

Revert "Issue #2004286 by joelpittet, jenlampton, Cottser, LinL: Defer calls to drupal_get_()* functions until printed inside a template by adding a RenderWrapper class."

This reverts commit 5aced021.

Issue #2004286 by joelpittet, jenlampton, Cottser, LinL: Defer calls to drupal_get_()* functions until printed inside a template by adding a RenderWrapper class.

Issue #2012812 by thedavidmeister, pwieck: drupal_render() can't distinguish between empty strings from theme() from an implemented hook and no hook being matched.

Issue #1754246 by webflo, swentel, penyaskito, andypost, alexpott, YesCT, dagmar: Languages should be configuration entities.

Issue #2015789 by fubhy, echoz, rteijeiro, LewisNyman, penyaskito: Remove language_css_alter() (RTL stylesheets) in favor of HTML 'dir' attribute.

Issue #1337554 by LewisNyman, Bojhan, YesCT, Cottser, jenlampton, Xano, David_Rothstein, larowlan, nilnullvoid: Develop and use separate branding for the installer.