Add a $joinedDescendants output specifier.

chrome/browser/resources/chromeos/chromevox/cvox2/background/live_regions.js

 // Copyright 2015 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 /**
  * @fileoverview Implements support for live regions in ChromeVox Next.
  */
 
 goog.provide('LiveRegions');
 
@@ skipping 111 matching lines @@
       return;
     }
 
     var range = cursors.Range.fromNode(node);
     var output = new Output();
     if (opt_prependFormatStr)
       output.format(opt_prependFormatStr);
     output.withSpeech(range, range, Output.EventType.NAVIGATE);
 
     if (!output.hasSpeech && node.liveAtomic)
-      output.format('$descendants', node);
+      output.format('$joinedDescendants', node);
 
     output.withSpeechCategory(cvox.TtsCategory.LIVE);
 
     if (!output.hasSpeech)
       return;
 
     // Enqueue live region updates that were received at approximately
     // the same time, otherwise flush previous live region updates.
     var currentTime = new Date();
     var queueTime = LiveRegions.LIVE_REGION_QUEUE_TIME_MS;
@@ skipping 11 matching lines @@
         return;
       parent = parent.parent;
     }
 
     this.liveRegionNodeSet_.add(node);
     output.go();
   },
 };
 
 });  // goog.scope