Add a test based on html5lib/html5lib-python#217

Author: gsnedders

tree-construction/adoption01.dat

@@ -335,3 +335,20 @@
 |         <b>
 |           <b>
 |             "x"
+
+#data
+<b><em><foo><foob><fooc><aside></b></em>
+#errors
+(1,35): adoption-agency-1.3
+(1,40): adoption-agency-1.3
+(1,40): expected-closing-tag-but-got-eof
+#document-fragment
+div
+#document
+| <b>
+|   <em>
+|     <foo>
+|       <foob>
+|         <fooc>
+| <aside>
+|   <b>