Editorial: Update use of WebIDL "invoke a callback function" (#172)

This algorithm can now handle the need to report an exception thrown by the callback. Some small tweaks are made for consistency with other specifications.

Part of whatwg/webidl#1425.

index.html

@@ -849,7 +849,7 @@ <h2>
                         <ol>
                           <li>[=Queue a task=] on the [=geolocation task
                           source=] with a step that [=invokes=]
-                          |successCallback| with |cachedPosition|.
+                          |successCallback| with « |cachedPosition| » and "`report`".
                           </li>
                           <li>Terminate this algorithm.
                           </li>
@@ -971,7 +971,8 @@ <h2>
                   <li>Stop the |timeout|.
                   </li>
                   <li>[=Queue a task=] on the [=geolocation task source=] with
-                  a step that [=invokes=] |successCallback| with |position|.
+                  a step that [=invokes=] |successCallback| with « |position| »
+                  and "`report`".
                   </li>
                 </ol>
               </li>
@@ -1043,7 +1044,7 @@ <h2>
           {{GeolocationPositionError/code}} attribute is initialized to |code|.
           </li>
           <li>[=Queue a task=] on the [=geolocation task source=] with a step
-          that [=invokes=] |callback| with |error|.
+          that [=invokes=] |callback| with « |error| » and "`report`".
           </li>
         </ol>
       </section>