Don't need to explicitly nullify dictionaries

Author: Michael Wilson

index.html

@@ -1227,7 +1227,7 @@ <h2 id="MIDIMessageEventInit">
           </h2>
           <pre class="idl">
           dictionary MIDIMessageEventInit: EventInit {
-            Uint8Array? data;
+            Uint8Array data;
           };
         </pre>
           <dl>
@@ -1301,7 +1301,7 @@ <h2 id="MIDIConnectionEventInit">
           </h2>
           <pre class="idl">
           dictionary MIDIConnectionEventInit: EventInit {
-            MIDIPort? port;
+            MIDIPort port;
           };
         </pre>
           <dl>