Complete ice server url validation

close #2912

amendments.json

@@ -55,7 +55,7 @@
     },
     {
       "description": "Use the url spec to parse ice server urls",
-      "pr": 2853,
+      "pr": [2853, 2996],
       "type": "correction",
       "status": "candidate",
       "id": 33

webrtc.html

@@ -3093,9 +3093,13 @@ <h4>
                       </li>
                       <li>
                         <p>If <var>parsedURL</var>'s [=url/query=] is non-null, run the following
-                        sub-steps:</p>
+                        sub-steps and if any of them fail, [=exception/throw=] a "{{SyntaxError}}" {{DOMException}} :</p>
                         <ol>
-                          <li><p>TODO: validate ?transport=udp|tcp</p></li>
+                          <li>Let <var>urlParams</var> be the result of applying <a data-cite="url#concept-urlencoded-string-parser"><code>application/x-www-form-urlencoded</code> string parser</a> to <var>parsedURL</var>'s [=url/query=].</li>
+			  <li>If <var>urlParams</var>’s [=list/size=] is greater than 1, then fail.</li>
+			  <li>If <var>urlParams</var>’s [=list/size=] is 1, let <code>(<var>paramName</var>, <var>paramValue</var>)</code> be the two items of <code><var>urlParams/var>[0]</code>.</li>
+			  <li>If <var>paramName</var> is set and different from <code>"transport"</code>, then fail.</li>
+			  <li>If <var>paramValue</var> is set and different from <code>"udp"</code> or <code>"tcp"</code>, then fail.</li>
                         </ol>
                       </li>
                       <li>