Update Compaction algorithm to re-initialize _container key_ by compacting _index key_ in step 12.8.9.6.

Fixes #406.

Author: gkellogg

index.html

@@ -3812,14 +3812,18 @@ <h3>Algorithm</h3>
                     <li>Otherwise, if <var>container</var> includes <code>@index</code>
                       and <var>index key</var> is <code>@index</code>,
                       set <var>map key</var> to the value of <code>@index</code> in <var>expanded item</var>, if any.</li>
-                    <li class="changed">Otherwise, if <var>container</var> includes <code>@index</code>
-                      and <var>index key</var> is not <code>@index</code>,
-                      set <var>map key</var> to the first value of <var>container key</var> in <var>compacted item</var>, if any.
-                      If there are remaining values in <var>compacted item</var>
-                      for <var>container key</var>, set the value of
-                      <var>container key</var> in <var>compacted item</var>
-                      to those remaining values. Otherwise, remove that
-                      <a>entry</a> from <var>compacted item</var>.
+                    <li id="alg-compact-2_8_9_6" class="changed">Otherwise, if <var>container</var> includes <code>@index</code>
+                      and <var>index key</var> is not <code>@index</code>:
+                      <ol>
+                        <li>Reinitialize <var>container key</var> by <a>IRI compacting</a>
+                          <var>index key</var>.</li>
+                        <li>Set <var>map key</var> to the first value of <var>container key</var> in <var>compacted item</var>, if any.</li>
+                        <li>If there are remaining values in <var>compacted item</var>
+                          for <var>container key</var>, set the value of
+                          <var>container key</var> in <var>compacted item</var>
+                          to those remaining values. Otherwise, remove that
+                          <a>entry</a> from <var>compacted item</var>.</li>
+                      </ol>
                     </li>
                     <li class="changed">Otherwise, if <var>container</var> includes <code>@id</code>, set
                       <var>map key</var> to the value of <var>container key</var> in