Convert theme_dropbutton_wrapper() to Twig

The only thing confusing me is the check for if dropbutton_wrapper is defined.

The render element should be fine, the Twig engine will handle rendering it. Looks like a good start, sending for review. Thanks @chrisjlee!

I don't see where dropbutton_wrapper would be defined, since it's not in the preprocess function. I haven't tested the patch but I think if you remove those lines we might see different test results.

Thanks again!

Literally the only thing I could find wrong with this:

+++ b/core/includes/theme.incundefined
@@ -3126,6 +3112,22 @@ function template_preprocess_region(&$variables) {
+ * Preprocess variables for a dropbutton wrapper template.

s/Preprocess/Prepares.

Other than that, RTBC :)

+++ b/core/includes/theme.incundefined
@@ -3126,6 +3112,22 @@ function template_preprocess_region(&$variables) {
+ * Default template: dropbutton-wrapper.html.twig

Oh, and this needs a period at the end. So two things :) Thanks guys!

This could use manual testing as well.

Thanks a bunch @chrisjlee! I missed these two before:

+++ b/core/includes/theme.incundefined
@@ -3126,6 +3112,22 @@ function template_preprocess_region(&$variables) {
+ * Prepares variables for a dropbutton wrapper template.

Prepares variables for dropbutton wrapper templates. (remove 'a', and plural templates at the end, missed this before).

+++ b/core/modules/system/templates/dropbutton-wrapper.html.twigundefined
@@ -0,0 +1,23 @@
+ * @see template_preprocess_dropdownbutton_wrapper()

template_preprocess_dropbutton_wrapper() - dropbutton instead of dropdownbutton.

Markup matches exactly, two tiny tweaks and then this is ready to go.

+++ b/core/modules/system/templates/dropbutton-wrapper.html.twigundefined
@@ -0,0 +1,23 @@
+ * Default theme implementation for a dropbutton menu.

I think this should say "for a dropbutton wrapper."

+++ b/core/modules/system/templates/dropbutton-wrapper.html.twigundefined
@@ -0,0 +1,23 @@
+{% spaceless %}
+{% if children %}
+  <div class="dropbutton-wrapper">
+    <div class="dropbutton-widget">
+      {{ children }}
+    </div>
+  </div>
+{% endif %}
+{% endspaceless %}

The contents of the {% spaceless %} tag should be indented per Twig coding standards.

The above would be a great Novice task.

Thanks @chrisjlee! RTBC once it comes back green.

Manual testing looks good, code and documentation look good, this is ready :)

Thanks everyone, especially @tim.plunkett, that's much better.

Working on profiling this one.

Numbers don't look so great for this one, performance will need some work.

Scenario: A simplified version of admin/content, displaying 50 dropbutton wrappers.

=== 8.x..8.x compared (51ff119b87ac8..51ff13036383a):

ct  : 108,200|108,200|0|0.0%
wt  : 460,107|459,457|-650|-0.1%
cpu : 413,141|414,199|1,058|0.3%
mu  : 16,384,728|16,384,728|0|0.0%
pmu : 16,481,400|16,481,400|0|0.0%

http://www.lionsad.de/xhprof-kit/xhprof/xhprof_html/?run1=51ff119b87ac8&...

=== 8.x..dropbutton-1939086-38 compared (51ff119b87ac8..51ff136e6df0a):

ct  : 108,200|110,138|1,938|1.8%
wt  : 460,107|465,904|5,797|1.3%
cpu : 413,141|419,799|6,658|1.6%
mu  : 16,384,728|16,426,480|41,752|0.3%
pmu : 16,481,400|16,516,480|35,080|0.2%

http://www.lionsad.de/xhprof-kit/xhprof/xhprof_html/?run1=51ff119b87ac8&...