Only invoke language map expansion if the value is a JSON object.

Author: gkellogg

spec/latest/json-ld-api/index.html

@@ -1097,7 +1097,7 @@ <h3>Expansion Algorithm</h3>
             If <em>property</em> is <code>@list</code> and any entry in <em>value</em> is a
             <tref>JSON object</tref> containing an <code>@list</code> property, return an error, as
             lists of lists are not supported.</li>
-          <li>Otherwise, if the <em>property</em> is not a keyword and its associated <tref>term</tref> entry in
+          <li>Otherwise, if <em>value</em> is a <tref>JSON object</tref> and <em>property</em> is not a keyword and its associated <tref>term</tref> entry in
           the <tref>active context</tref> has a <code>@container</code> key associated with a value of <code>@language</code>,
           process the associated <em>value</em> as a <em>language map</em>:
             <ol class="algorithm">