dense list items that follow sparse ones should not be rendered as sparse ones

Parsedown.php

@@ -200,13 +200,14 @@ class Parsedown
 
                         $blocks []= $block;
 
-                        unset($block['first']);
-
                         $block['last'] = true;
                         $block['lines'] = array();
 
                         $block['lines'] []= preg_replace('/^[ ]{0,4}/', '', $matches[1]);
 
+                        unset($block['first']);
+                        unset($block['interrupted']);
+
                         continue 2;
                     }
 

tests/data/sparse_dense_list.html

@@ -0,0 +1,7 @@
+<ul>
+<li>
+<p>li</p>
+</li>
+<li>li</li>
+<li>li</li>
+</ul>

tests/data/sparse_dense_list.md

@@ -0,0 +1,4 @@
+- li
+
+- li
+- li