Export performance entry buffer

Fixes #196

Author: npm1

index.html

@@ -229,7 +229,7 @@ <h2><dfn>Performance Timeline</dfn></h2>
       "infra">map</a>'s <a data-cite="INFRA#map-value">value</a> is the
       following tuple:
         <ul>
-          <li>A <dfn>performance entry buffer</dfn> to store
+          <li>A <dfn class="export">performance entry buffer</dfn> to store
           <a>PerformanceEntry</a> objects, that is initially empty.
           </li>
           <li>An integer <dfn>maxBufferSize</dfn>, initialized to the