Remove usage of drupal_html_class() and drupal_clean_css_identifier()

I agree with #5, that is unnecessary, and we have loads of places where we just add a hard-coded string to ['class'].

There are also lots of calls to drupal_clean_css_identifier(), which is basically the same function but without static caching and strtolower. Given the patch is only 20k I think it would be worth doing those too (it's also deprecated).

Looks good, there was just one instance that was missed, which I've fixed in the attached patch.

Other than that I'd mark it RTBC, so @rpayanm if you're happy with my change I think you'd be allowed to mark it RTBC (other reviewers welcome too of course).

Ohhh yes! I searched for drupal_html_class( and drupal_clean_css_identifier(. Nice catch. Looks good for me :)

I read the patch, and it looks like a good one-to-one replacement. Not changing status, but a few nits

1. +++ b/core/includes/theme.inc
   @@ -1352,7 +1353,7 @@ function template_preprocess_html(&$variables) {
   +    $variables['attributes']['class'][] = 'path-' . Html::getClass($segment[1]);
      }
   

   Since things are being touched, though, there is some inconsistent usage of the method. Other places have all of the class parts in the method call. Consistent use may be a good idea.

2. +++ b/core/modules/file/src/Tests/FileFieldWidgetTest.php
   @@ -74,7 +75,7 @@ function testSingleValuedWidget() {
   +      $label = $this->xpath("//label[@for='edit-" . Html::cleanCssIdentifier($field_name) . "-0-upload']");
          $this->assertTrue(isset($label[0]), 'Label for upload found.');
   

   This should probably use the $arguments parameter to ->xpath() and single quotes.

#10.1 The function takes an unknown string and converts it to a valid class name. We already know 'path-' is a valid (partial) class name, so there's no need to do the conversion on that. The function uses a static cache, so by not passing that partial you may even get a higher cache hit rate. I don't imagine the performance impact is huge, but these are functions that might be called a lot. Either way it's not something I'd personally worry about changing without a good reason.

#10.2 Yeah I guess that's technically better

#11-1, I get that. It was more a comment that the usage is inconsistent:

+++ b/core/includes/theme.inc
@@ -1352,7 +1353,7 @@ function template_preprocess_html(&$variables) {
+    $variables['attributes']['class'][] = 'path-' . Html::getClass($segment[1]);
   }

String concatenation outside method invokation.

+++ b/core/modules/block/src/Tests/BlockRenderOrderTest.php
@@ -74,7 +75,7 @@ function testBlockRenderOrder() {
+        $position[$id] = strpos($test_content, Html::getClass('block-' . $test_blocks[$id]['id']));

String concatenation as part of method invokation.

It's just a nit, though; I should have posted both examples in my first comment.

Reroll, just one easy conflict resolved:

+++ b/core/modules/block_content/src/BlockContentForm.php
@@ -102,7 +103,7 @@ public function form(array $form, FormStateInterface $form_state) {
-    $form['#attributes']['class'][0] = drupal_html_class('block-' . $block->bundle() . '-form');
+    $form['#attributes']['class'][0] = 'block-' . Html::getClass($block->bundle()) . '-form';

Committed fdec77f and pushed to 8.0.x. Thanks!

This issue is a prioritized change (removal of deprecated function use) as per https://www.drupal.org/core/beta-changes and it's benefits outweigh any disruption.

diff --git a/core/themes/seven/seven.theme b/core/themes/seven/seven.theme
index 39149e6..8e78d77 100644
--- a/core/themes/seven/seven.theme
+++ b/core/themes/seven/seven.theme
@@ -5,7 +5,6 @@
  * Functions to support theming in the Seven theme.
  */
 
-use Drupal\Component\Utility\Html;
 use Drupal\Component\Utility\Xss;
 use Drupal\Component\Utility\String;
 use Drupal\Core\Form\FormStateInterface;

This use was not used. Fixed on commit.