[css-transitions] Fix transition event linking

1) Change the id events to just "transitionend" etc. (this is the
convention used in the currently published WD)
2) Change the location of the definition to the actual spot where it is
defined not the spot where we define the on* handlers.

Author: birtles

css-transitions/Overview.bs

@@ -1240,7 +1240,7 @@ Types of <code>TransitionEvent</code> {#event-transitionevent}
 The different types of transition events that can occur are:
 
   <dl dfn-type=event dfn-for=transitionevent>
-    <dt><dfn>transitionrun</dfn></dt>
+    <dt><dfn id=transitionrun>transitionrun</dfn></dt>
     <dd>
       The {{transitionrun}} event occurs when a transition is created (i.e.,
       when it is added to the set of <a>running transitions</a>).
@@ -1257,7 +1257,7 @@ The different types of transition events that can occur are:
       </ul>
     </dd>
 
-    <dt><dfn>transitionstart</dfn></dt>
+    <dt><dfn id=transitionstart>transitionstart</dfn></dt>
     <dd>
       The {{transitionstart}} event occurs when a transition's delay phase ends.
 
@@ -1270,7 +1270,7 @@ The different types of transition events that can occur are:
       </ul>
     </dd>
 
-    <dt><dfn>transitionend</dfn></dt>
+    <dt><dfn id=transitionend>transitionend</dfn></dt>
     <dd>
       The {{transitionend}} event occurs at the completion of the transition. In
       the case where a transition is removed before completion, such as if the
@@ -1285,7 +1285,7 @@ The different types of transition events that can occur are:
       </ul>
     </dd>
 
-    <dt><dfn>transitioncancel</dfn></dt>
+    <dt><dfn id=transitioncancel>transitioncancel</dfn></dt>
     <dd>
       The {{transitioncancel}} event occurs when a transition is <a
       lt="cancel">cancelled</a>.
@@ -1323,19 +1323,19 @@ objects, as <a>event handler IDL attributes</a>:
   </tr>
   <tr>
     <td><dfn>ontransitionrun</dfn></td>
-    <td><dfn><a idl>transitionrun</a></dfn></td>
+    <td><a idl>transitionrun</a></td>
   </tr>
   <tr>
     <td><dfn>ontransitionstart</dfn></td>
-    <td><dfn><a idl>transitionstart</a></dfn></td>
+    <td><a idl>transitionstart</a></td>
   </tr>
   <tr>
     <td><dfn>ontransitionend</dfn></td>
-    <td><dfn><a idl>transitionend</a></dfn></td>
+    <td><a idl>transitionend</a></td>
   </tr>
   <tr>
     <td><dfn>ontransitioncancel</dfn></td>
-    <td><dfn><a idl>transitioncancel</a></dfn></td>
+    <td><a idl>transitioncancel</a></td>
   </tr>
 </table>