Remove circle from HTML_VOID_ELEMENTS set.

`<circle>` is in the SVG_SELF_CLOSING_ELEMENTS list and is not a void element according to
'https://html.spec.whatwg.org/multipage/syntax.html#void-elements'.

Author: davekaro

actionview/lib/action_view/helpers/tag_helper.rb

@@ -45,7 +45,7 @@ class TagBuilder # :nodoc:
         include CaptureHelper
         include OutputSafetyHelper
 
-        HTML_VOID_ELEMENTS = %i(area base br col circle embed hr img input keygen link meta param source track wbr).to_set
+        HTML_VOID_ELEMENTS = %i(area base br col embed hr img input keygen link meta param source track wbr).to_set
         SVG_SELF_CLOSING_ELEMENTS = %i(animate animateMotion animateTransform circle ellipse line path polygon polyline rect set stop use view).to_set
 
         def initialize(view_context)

actionview/test/template/tag_helper_test.rb

@@ -21,13 +21,21 @@ def test_tag_builder
   def test_tag_builder_void_tag
     assert_equal "<br>", tag.br
     assert_equal "<br class=\"some_class\">", tag.br(class: "some_class")
-    assert_equal "<svg><use href=\"#cool-icon\" /></svg>", tag.svg { tag.use("href" => "#cool-icon") }
   end
 
   def test_tag_builder_void_tag_with_forced_content
     assert_equal "<br>some content</br>", tag.br("some content")
   end
 
+  def test_tag_builder_self_closing_tag
+    assert_equal "<svg><use href=\"#cool-icon\" /></svg>", tag.svg { tag.use("href" => "#cool-icon") }
+    assert_equal "<svg><circle cx=\"5\" cy=\"5\" r=\"5\" /></svg>", tag.svg { tag.circle(cx: "5", cy: "5", r: "5") }
+  end
+
+  def test_tag_builder_self_closing_tag_with_content
+    assert_equal "<svg><circle><desc>A circle</desc></circle></svg>", tag.svg { tag.circle { tag.desc "A circle" } }
+  end
+
   def test_tag_builder_is_singleton
     assert_equal tag, tag
   end