4.x: Refactor footer menus so that they do not render elements if empty, r…

[robgasc]

…emove bonus block templates that are overriding a bootstrap template by directly replacing the offending template in our theme, and clear up nav element use to ensure major navs are using the element.

Addresses #1113

Testing steps

1. Download an existing site.
2. Compare the two menus between the local site and remove site.
3. Ensure they are matching.
4. Remove the existing footer menu items from the local site.
5. Inspect the footer and verify no vestige of the footer menu elements remains.

[robgasc]

This is a fairly large refactor of the footer menu.

I tried to remove extra templates here by using a direct override of the bootstrap template, where for whatever reason bootstrap applies an h5 to blocks. It also removes the nav element altogether, and the use of aria-labels, as the menu blocks already have headings for their labels. This also results in a minor style change to move the margin bottom onto the footer-menus class instead of the nav, since it also bumps following elements down appropriately.

[robgasc]

This PR and its sibling will hide the container for menu 1 and 2, so if there is value in having the container, this will break that piece. For instance, adding a spacing between the 3/4 menu and the address area.

[trubach]

I'm seeing a WSOD error when I tested out this branch on my local dev against a copy of the drupal.webtheme website.

Steps I followed:

1. Get a local copy of drupal.webtheme running on my local dev running the 4.x branch
2. Deleted the items in the footer menu third menu to make it a blank menu
3. Switched the theme repo to the 1113-empty-footer-menus-use branch
4. Cleared cache
5. Homepage throws WSOD (output below)

Here's the output of the error message:

The website encountered an unexpected error. Try again later.

Twig\Error\SyntaxError: Unexpected end of template in "themes/contrib/illinois_framework_theme/templates/region/region--footer.html.twig" at line 162. in Twig\TokenStream->next() (line 162 of /app/src/illinois_framework_theme/templates/region/region--footer.html.twig).
Twig\TokenParser\IfTokenParser->parse(Object) (Line: 224)
Twig\Parser->subparse(NULL, ) (Line: 104)
Twig\Parser->parse(Object) (Line: 558)
Twig\Environment->parse(Object) (Line: 589)
Twig\Environment->compileSource(Object) (Line: 131)
Drupal\Core\Template\TwigEnvironment->compileSource(Object) (Line: 408)
Twig\Environment->loadTemplate('__TwigTemplate_eefbbe4333df18c7b5ed22670d800c46', 'themes/contrib/illinois_framework_theme/templates/region/region--footer.html.twig') (Line: 370)
Twig\Environment->load('themes/contrib/illinois_framework_theme/templates/region/region--footer.html.twig') (Line: 33)
twig_render_template('themes/contrib/illinois_framework_theme/templates/region/region--footer.html.twig', Array) (Line: 348)
Drupal\Core\Theme\ThemeManager->render('region', Array) (Line: 546)
Drupal\Core\Render\Renderer->doRender(Array, ) (Line: 248)
Drupal\Core\Render\Renderer->render(Array) (Line: 484)
Drupal\Core\Template\TwigExtension->escapeFilter(Object, Array, 'html', NULL, 1) (Line: 229)
__TwigTemplate_738ce642dbe5d1219603ccf728096fbe->doDisplay(Array, Array) (Line: 402)
Twig\Template->yield(Array, Array) (Line: 358)
Twig\Template->display(Array) (Line: 373)
Twig\Template->render(Array) (Line: 51)
Twig\TemplateWrapper->render(Array) (Line: 33)
twig_render_template('themes/contrib/illinois_framework_theme/templates/layout/page--content-page.html.twig', Array) (Line: 348)
Drupal\Core\Theme\ThemeManager->render('page', Array) (Line: 490)
Drupal\Core\Render\Renderer->doRender(Array, ) (Line: 248)
Drupal\Core\Render\Renderer->render(Array) (Line: 484)
Drupal\Core\Template\TwigExtension->escapeFilter(Object, Array, 'html', NULL, 1) (Line: 103)
__TwigTemplate_6995afac8d7e5573e534f8b38c9db8b8->doDisplay(Array, Array) (Line: 402)
Twig\Template->yield(Array, Array) (Line: 358)
Twig\Template->display(Array) (Line: 373)
Twig\Template->render(Array) (Line: 51)
Twig\TemplateWrapper->render(Array) (Line: 33)
twig_render_template('themes/contrib/illinois_framework_theme/templates/layout/html.html.twig', Array) (Line: 348)
Drupal\Core\Theme\ThemeManager->render('html', Array) (Line: 490)
Drupal\Core\Render\Renderer->doRender(Array, ) (Line: 248)
Drupal\Core\Render\Renderer->render(Array) (Line: 158)
Drupal\Core\Render\MainContent\HtmlRenderer->Drupal\Core\Render\MainContent\{closure}() (Line: 637)
Drupal\Core\Render\Renderer->executeInRenderContext(Object, Object) (Line: 153)
Drupal\Core\Render\MainContent\HtmlRenderer->renderResponse(Array, Object, Object) (Line: 90)
Drupal\Core\EventSubscriber\MainContentViewSubscriber->onViewRenderArray(Object, 'kernel.view', Object)
call_user_func(Array, Object, 'kernel.view', Object) (Line: 111)
Drupal\Component\EventDispatcher\ContainerAwareEventDispatcher->dispatch(Object, 'kernel.view') (Line: 186)
Symfony\Component\HttpKernel\HttpKernel->handleRaw(Object, 1) (Line: 76)
Symfony\Component\HttpKernel\HttpKernel->handle(Object, 1, 1) (Line: 53)
Drupal\Core\StackMiddleware\Session->handle(Object, 1, 1) (Line: 48)
Drupal\Core\StackMiddleware\KernelPreHandle->handle(Object, 1, 1) (Line: 28)
Drupal\Core\StackMiddleware\ContentLength->handle(Object, 1, 1) (Line: 116)
Drupal\page_cache\StackMiddleware\PageCache->pass(Object, 1, 1) (Line: 90)
Drupal\page_cache\StackMiddleware\PageCache->handle(Object, 1, 1) (Line: 48)
Drupal\Core\StackMiddleware\ReverseProxyMiddleware->handle(Object, 1, 1) (Line: 51)
Drupal\Core\StackMiddleware\NegotiationMiddleware->handle(Object, 1, 1) (Line: 36)
Drupal\Core\StackMiddleware\AjaxPageState->handle(Object, 1, 1) (Line: 51)
Drupal\Core\StackMiddleware\StackedHttpKernel->handle(Object, 1, 1) (Line: 741)
Drupal\Core\DrupalKernel->handle(Object) (Line: 19)

[trubach]

Tested the changes on a copy of the drupal.webtheme site on my localdev and verified that the empty <nav> element no longer appears.

Approved!